diff --git a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/StringOperators.java b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/StringOperators.java
index 8b6bb03875..19d14bdb44 100644
--- a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/StringOperators.java
+++ b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/StringOperators.java
@@ -686,10 +686,28 @@ public RegexMatch regexMatch(String regex, String options) {
 		private RegexMatch createRegexMatch() {
 			return usesFieldRef() ? RegexMatch.valueOf(fieldReference) : RegexMatch.valueOf(expression);
 		}
+		
+		public ReplaceOne replaceOne(String find,String replacement) {
+			return createReplaceOne().find(find).replacement(replacement);
+		}
+		
+		private ReplaceOne createReplaceOne() {
+			return usesFieldRef() ? ReplaceOne.valueOf(fieldReference) : ReplaceOne.valueOf(expression);
+		}
+		
+		public ReplaceAll replaceAll(String find,String replacement) {
+			return createReplaceAll().find(find).replacement(replacement);
+		}
+		
+		private ReplaceAll createReplaceAll() {
+			return usesFieldRef() ? ReplaceAll.valueOf(fieldReference) : ReplaceAll.valueOf(expression);
+		}
 
 		private boolean usesFieldRef() {
 			return fieldReference != null;
 		}
+		
+		
 	}
 
 	/**
@@ -2078,4 +2096,260 @@ protected String getMongoMethod() {
 			return "$regexMatch";
 		}
 	}
+	
+	/**
+	 * {@link AggregationExpression} for {@code $replaceOne} which replaces the first instance of a search string in an
+	 * input string with a replacement string. <br />
+	 * <strong>NOTE:</strong> Requires MongoDB 4.4 or later.
+	 */
+	public static class ReplaceOne extends AbstractAggregationExpression {
+
+		protected ReplaceOne(Object value) {
+			super(value);
+		}
+
+		/**
+		 * Creates new {@link ReplaceOne} using the value of the provided {@link Field fieldReference} as {@literal input}
+		 * value.
+		 *
+		 * @param fieldReference must not be {@literal null}.
+		 * @return new instance of {@link ReplaceOne}.
+		 */
+		public static ReplaceOne valueOf(String fieldReference) {
+
+			Assert.notNull(fieldReference, "FieldReference must not be null!");
+
+			return new ReplaceOne(Collections.singletonMap("input", Fields.field(fieldReference)));
+		}
+
+		/**
+		 * Creates new {@link ReplaceOne} using the result of the provided {@link AggregationExpression} as {@literal input}
+		 * value.
+		 *
+		 * @param expression must not be {@literal null}.
+		 * @return new instance of {@link ReplaceOne}.
+		 */
+		public static ReplaceOne valueOf(AggregationExpression expression) {
+
+			Assert.notNull(expression, "Expression must not be null!");
+
+			return new ReplaceOne(Collections.singletonMap("input", expression));
+		}
+
+		/**
+		 * The string to use to replace the first matched instance of {@code find} in input.
+		 *
+		 * @param replacement must not be {@literal null}.
+		 * @return new instance of {@link ReplaceOne}.
+		 */
+		public ReplaceOne replacement(String replacement) {
+
+			Assert.notNull(replacement, "Replacement must not be null!");
+
+			return new ReplaceOne(append("replacement", replacement));
+		}
+
+		/**
+		 * Specifies the reference to the {@link Field field} holding the string to use to replace the first matched
+		 * instance of {@code find} in input.
+		 *
+		 * @param fieldReference must not be {@literal null}.
+		 * @return new instance of {@link ReplaceOne}.
+		 */
+		public ReplaceOne replacementOf(String fieldReference) {
+
+			Assert.notNull(fieldReference, "FieldReference must not be null!");
+
+			return new ReplaceOne(append("replacement", Fields.field(fieldReference)));
+		}
+
+		/**
+		 * Specifies the {@link AggregationExpression} evaluating to the string to use to replace the first matched instance
+		 * of {@code find} in {@code input}.
+		 *
+		 * @param expression must not be {@literal null}.
+		 * @return new instance of {@link ReplaceOne}.
+		 */
+		public ReplaceOne replacementOf(AggregationExpression expression) {
+
+			Assert.notNull(expression, "Expression must not be null!");
+
+			return new ReplaceOne(append("replacement", expression));
+		}
+
+		/**
+		 * The string to search for within the given input field.
+		 *
+		 * @param find must not be {@literal null}.
+		 * @return new instance of {@link ReplaceOne}.
+		 */
+		public ReplaceOne find(String searchStr) {
+
+			Assert.notNull(searchStr, "Search string must not be null!");
+
+			Map<String, Object> search = append("find", searchStr);
+
+			return new ReplaceOne(search);
+		}
+
+		/**
+		 * Specify the reference to the {@link Field field} holding the string to search for within the given input field.
+		 *
+		 * @param find must not be {@literal null}.
+		 * @return new instance of {@link ReplaceOne}.
+		 */
+		public ReplaceOne findOf(String fieldReference) {
+
+			Assert.notNull(fieldReference, "fieldReference must not be null!");
+
+			return new ReplaceOne(append("find", fieldReference));
+		}
+
+		/**
+		 * Specify the {@link AggregationExpression} evaluating to the the string to search for within the given input
+		 * field.
+		 *
+		 * @param expression must not be {@literal null}.
+		 * @return new instance of {@link ReplaceOne}.
+		 */
+		public ReplaceOne findOf(AggregationExpression expression) {
+
+			Assert.notNull(expression, "Expression must not be null!");
+
+			return new ReplaceOne(append("find", expression));
+		}
+
+		@Override
+		protected String getMongoMethod() {
+			return "$replaceOne";
+		}
+	}
+	
+	/**
+	 * {@link AggregationExpression} for {@code $replaceAll} which replaces all instances of a search string in an input
+	 * string with a replacement string. <br />
+	 * <strong>NOTE:</strong> Requires MongoDB 4.4 or later.
+	 */
+	public static class ReplaceAll extends AbstractAggregationExpression {
+
+		protected ReplaceAll(Object value) {
+			super(value);
+		}
+
+		/**
+		 * Creates new {@link ReplaceAll} using the value of the provided {@link Field fieldReference} as {@literal input}
+		 * value.
+		 *
+		 * @param fieldReference must not be {@literal null}.
+		 * @return new instance of {@link ReplaceAll}.
+		 */
+		public static ReplaceAll valueOf(String fieldReference) {
+
+			Assert.notNull(fieldReference, "FieldReference must not be null!");
+
+			return new ReplaceAll(Collections.singletonMap("input", Fields.field(fieldReference)));
+		}
+
+		/**
+		 * Creates new {@link ReplaceAll} using the result of the provided {@link AggregationExpression} as {@literal input}
+		 * value.
+		 *
+		 * @param expression must not be {@literal null}.
+		 * @return new instance of {@link ReplaceAll}.
+		 */
+		public static ReplaceAll valueOf(AggregationExpression expression) {
+
+			Assert.notNull(expression, "Expression must not be null!");
+
+			return new ReplaceAll(Collections.singletonMap("input", expression));
+		}
+
+		/**
+		 * The string to use to replace the first matched instance of {@code find} in input.
+		 *
+		 * @param replacement must not be {@literal null}.
+		 * @return new instance of {@link ReplaceAll}.
+		 */
+		public ReplaceAll replacement(String replacement) {
+
+			Assert.notNull(replacement, "Replacement must not be null!");
+
+			return new ReplaceAll(append("replacement", replacement));
+		}
+
+		/**
+		 * Specifies the reference to the {@link Field field} holding the string to use to replace the first matched
+		 * instance of {@code find} in input.
+		 *
+		 * @param fieldReference must not be {@literal null}.
+		 * @return new instance of {@link ReplaceAll}.
+		 */
+		public ReplaceAll replacementOf(String fieldReference) {
+
+			Assert.notNull(fieldReference, "FieldReference must not be null!");
+
+			return new ReplaceAll(append("replacement", Fields.field(fieldReference)));
+		}
+
+		/**
+		 * Specifies the {@link AggregationExpression} evaluating to the string to use to replace the first matched instance
+		 * of {@code find} in input.
+		 *
+		 * @param expression must not be {@literal null}.
+		 * @return new instance of {@link ReplaceAll}.
+		 */
+		public ReplaceAll replacementOf(AggregationExpression expression) {
+
+			Assert.notNull(expression, "Expression must not be null!");
+
+			return new ReplaceAll(append("replacement", expression));
+		}
+
+		/**
+		 * The string to search for within the given input field.
+		 *
+		 * @param find must not be {@literal null}.
+		 * @return new instance of {@link ReplaceAll}.
+		 */
+		public ReplaceAll find(String searchStr) {
+
+			Assert.notNull(searchStr, "Search string must not be null!");
+
+			Map<String, Object> search = append("find", searchStr);
+
+			return new ReplaceAll(search);
+		}
+
+		/**
+		 * Specify the reference to the {@link Field field} holding the string to search for within the given input field.
+		 *
+		 * @param find must not be {@literal null}.
+		 * @return new instance of {@link ReplaceAll}.
+		 */
+		public ReplaceAll findOf(String fieldReference) {
+
+			Assert.notNull(fieldReference, "fieldReference must not be null!");
+
+			return new ReplaceAll(append("find", fieldReference));
+		}
+
+		/**
+		 * Specify the {@link AggregationExpression} evaluating to the string to search for within the given input field.
+		 *
+		 * @param expression must not be {@literal null}.
+		 * @return new instance of {@link ReplaceAll}.
+		 */
+		public ReplaceAll findOf(AggregationExpression expression) {
+
+			Assert.notNull(expression, "Expression must not be null!");
+
+			return new ReplaceAll(append("find", expression));
+		}
+
+		@Override
+		protected String getMongoMethod() {
+			return "$replaceAll";
+		}
+	}
+
 }
diff --git a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/spel/MethodReferenceNode.java b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/spel/MethodReferenceNode.java
index dc7a3cc982..5d9e839ae0 100644
--- a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/spel/MethodReferenceNode.java
+++ b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/spel/MethodReferenceNode.java
@@ -124,6 +124,8 @@ public class MethodReferenceNode extends ExpressionNode {
 		map.put("regexFind", mapArgRef().forOperator("$regexFind").mappingParametersTo("input", "regex" , "options"));
 		map.put("regexFindAll", mapArgRef().forOperator("$regexFindAll").mappingParametersTo("input", "regex" , "options"));
 		map.put("regexMatch", mapArgRef().forOperator("$regexMatch").mappingParametersTo("input", "regex" , "options"));
+		map.put("replaceOne", mapArgRef().forOperator("$replaceOne").mappingParametersTo("input", "find" , "replacement"));
+		map.put("replaceAll", mapArgRef().forOperator("$replaceAll").mappingParametersTo("input", "find" , "replacement"));
 
 		// TEXT SEARCH OPERATORS
 		map.put("meta", singleArgRef().forOperator("$meta"));
diff --git a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/aggregation/SpelExpressionTransformerUnitTests.java b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/aggregation/SpelExpressionTransformerUnitTests.java
index 899e02a172..fd4aa70988 100644
--- a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/aggregation/SpelExpressionTransformerUnitTests.java
+++ b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/aggregation/SpelExpressionTransformerUnitTests.java
@@ -864,6 +864,20 @@ void shouldRenderRegexMatchWithOptionsFromFieldReference() {
 		assertThat(transform("regexMatch(field1,'e',field2)"))
 				.isEqualTo("{ \"$regexMatch\" : {\"input\" : \"$field1\" , \"regex\" : \"e\" , \"options\" : \"$field2\"}}");
 	}
+	
+	@Test 
+	void shouldRenderReplaceOne() {
+
+		assertThat(transform("replaceOne(field,'bar','baz')"))
+				.isEqualTo("{ \"$replaceOne\" : {\"input\" : \"$field\" , \"find\" : \"bar\" , \"replacement\" : \"baz\"}}");
+	}
+
+	@Test 
+	void shouldRenderReplaceAll() {
+
+		assertThat(transform("replaceAll(field,'bar','baz')"))
+				.isEqualTo("{ \"$replaceAll\" : {\"input\" : \"$field\" , \"find\" : \"bar\" , \"replacement\" : \"baz\"}}");
+	}
 
 
 	@Test // DATAMONGO-2077
diff --git a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/aggregation/StringOperatorsUnitTests.java b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/aggregation/StringOperatorsUnitTests.java
index d8ba5129e0..35f9611fc5 100644
--- a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/aggregation/StringOperatorsUnitTests.java
+++ b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/aggregation/StringOperatorsUnitTests.java
@@ -281,4 +281,35 @@ void shouldRenderRegexFindWithOptionsExpression() {
 				.isEqualTo("{ $regexFind: { \"input\" : \"$shrewd\", \"regex\" : \"e\" , \"options\" : " + EXPRESSION_STRING
 						+ " } } ");
 	}
+	
+	@Test 
+	void shouldRenderReplaceOne() {
+
+		assertThat(StringOperators.valueOf("bar").replaceOne("foobar","baz").toDocument(Aggregation.DEFAULT_CONTEXT))
+				.isEqualTo("{ $replaceOne : {\"find\" : \"foobar\", \"input\" : \"$bar\", \"replacement\" : \"baz\"}}");
+	}
+
+	@Test
+	void shouldRenderReplaceOneForExpression() {
+
+		assertThat(StringOperators.valueOf(EXPRESSION).replaceOne("a","s").toDocument(Aggregation.DEFAULT_CONTEXT))
+				.isEqualTo("{ $replaceOne : {\"find\" : \"a\", \"input\" : " + EXPRESSION_STRING + ", \"replacement\" : \"s\"}}");
+	}
+	
+	@Test 
+	void shouldRenderReplaceAll() {
+
+		assertThat(StringOperators.valueOf("bar").replaceAll("foobar","baz").toDocument(Aggregation.DEFAULT_CONTEXT))
+				.isEqualTo("{ $replaceAll : {\"find\" : \"foobar\", \"input\" : \"$bar\", \"replacement\" : \"baz\"}}");
+	}
+
+	@Test
+	void shouldRenderReplaceAllForExpression() {
+
+		assertThat(StringOperators.valueOf(EXPRESSION).replaceAll("a","s").toDocument(Aggregation.DEFAULT_CONTEXT))
+				.isEqualTo("{ $replaceAll : {\"find\" : \"a\", \"input\" : " + EXPRESSION_STRING + ", \"replacement\" : \"s\"}}");
+	}
+
+
+
 }
diff --git a/spring-data-mongodb/src/test/resources/reactive-infrastructure.xml b/spring-data-mongodb/src/test/resources/reactive-infrastructure.xml
index 896bb26812..1abf2324bf 100644
--- a/spring-data-mongodb/src/test/resources/reactive-infrastructure.xml
+++ b/spring-data-mongodb/src/test/resources/reactive-infrastructure.xml
@@ -5,7 +5,7 @@
 
 	<bean id="mongoClient" class="org.springframework.data.mongodb.core.ReactiveMongoClientFactoryBean">
 		<property name="host" value="127.0.0.1"/>
-		<property name="port" value="27017"/>
+		<property name="port" value="27018"/>
 	</bean>
 
 	<bean id="reactiveMongoDbFactory" class="org.springframework.data.mongodb.core.SimpleReactiveMongoDatabaseFactory">