diff --git a/lldb/packages/Python/lldbsuite/test/dotest.py b/lldb/packages/Python/lldbsuite/test/dotest.py
index f14a00a2394b0..aa9581a0aedc2 100644
--- a/lldb/packages/Python/lldbsuite/test/dotest.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest.py
@@ -219,6 +219,10 @@ def parseOptionsAndInitTestdirs():
     except:
         raise
 
+    if args.dll_directory:
+        for dir in args.dll_directory:
+            os.add_dll_directory(dir)
+
     if args.unset_env_varnames:
         for env_var in args.unset_env_varnames:
             if env_var in os.environ:
diff --git a/lldb/packages/Python/lldbsuite/test/dotest_args.py b/lldb/packages/Python/lldbsuite/test/dotest_args.py
index a80428ebec589..cdcc659df61b1 100644
--- a/lldb/packages/Python/lldbsuite/test/dotest_args.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest_args.py
@@ -321,6 +321,12 @@ def create_parser():
         action="append",
         help="Specify an environment variable to set to the given value for the inferior.",
     )
+    # See https://docs.python.org/3.8/whatsnew/3.8.html#bpo-36085-whatsnew.
+    group.add_argument(
+        "--dll-directory",
+        action="append",
+        help="Specify a directory to include when searching for .dll files. This can be passed multiple times.",
+    )
     X(
         "-v",
         "Do verbose mode of unittest framework (print out each test case invocation)",