diff --git a/nipype/algorithms/misc.py b/nipype/algorithms/misc.py
index 48b45e6e01..3df52cf3f8 100644
--- a/nipype/algorithms/misc.py
+++ b/nipype/algorithms/misc.py
@@ -447,8 +447,8 @@ def _list_outputs(self):
 
 
 class TSNRInputSpec(BaseInterfaceInputSpec):
-    in_file = File(exists=True, mandatory=True,
-                   desc='realigned 4D file')
+    in_file = InputMultiPath(File(exists=True), mandatory=True,
+                   desc='realigned 4D file or a list of 3D files')
     regress_poly = traits.Int(min=1, desc='Remove polynomials')
 
 
@@ -475,39 +475,40 @@ class TSNR(BaseInterface):
     input_spec = TSNRInputSpec
     output_spec = TSNROutputSpec
 
-    def _gen_output_file_name(self, out_ext=None):
-        _, base, _ = split_filename(self.inputs.in_file)
-        if out_ext in ['mean', 'stddev']:
-            return os.path.abspath(base + "_tsnr_" + out_ext + ".nii.gz")
-        elif out_ext in ['detrended']:
-            return os.path.abspath(base + "_" + out_ext + ".nii.gz")
+    def _gen_output_file_name(self, suffix=None):
+        _, base, ext = split_filename(self.inputs.in_file[0])
+        if suffix in ['mean', 'stddev']:
+            return os.path.abspath(base + "_tsnr_" + suffix + ext)
+        elif suffix in ['detrended']:
+            return os.path.abspath(base + "_" + suffix + ext)
         else:
-            return os.path.abspath(base + "_tsnr.nii.gz")
+            return os.path.abspath(base + "_tsnr" + ext)
 
     def _run_interface(self, runtime):
-        img = nb.load(self.inputs.in_file)
-        data = img.get_data()
+        img = nb.load(self.inputs.in_file[0])
+        vollist = [nb.load(filename) for filename in self.inputs.in_file]
+        data = np.concatenate([vol.get_data().reshape(vol.get_shape()[:3] + (-1,)) for vol in vollist], axis=3)
         if isdefined(self.inputs.regress_poly):
             timepoints = img.get_shape()[-1]
-            X = np.ones((timepoints,1))
+            X = np.ones((timepoints, 1))
             for i in range(self.inputs.regress_poly):
-                X = np.hstack((X,legendre(i+1)(np.linspace(-1, 1, timepoints))[:, None]))
+                X = np.hstack((X, legendre(i + 1)(np.linspace(-1, 1, timepoints))[:, None]))
             betas = np.dot(np.linalg.pinv(X), np.rollaxis(data, 3, 2))
-            datahat = np.rollaxis(np.dot(X[:,1:],
+            datahat = np.rollaxis(np.dot(X[:, 1:],
                                          np.rollaxis(betas[1:, :, :, :], 0, 3)),
                                   0, 4)
             data = data - datahat
             img = nb.Nifti1Image(data, img.get_affine(), img.get_header())
-            nb.save(img,  self._gen_output_file_name('detrended'))
+            nb.save(img, self._gen_output_file_name('detrended'))
         meanimg = np.mean(data, axis=3)
         stddevimg = np.std(data, axis=3)
-        tsnr = meanimg/stddevimg
+        tsnr = meanimg / stddevimg
         img = nb.Nifti1Image(tsnr, img.get_affine(), img.get_header())
-        nb.save(img,  self._gen_output_file_name())
+        nb.save(img, self._gen_output_file_name())
         img = nb.Nifti1Image(meanimg, img.get_affine(), img.get_header())
-        nb.save(img,  self._gen_output_file_name('mean'))
+        nb.save(img, self._gen_output_file_name('mean'))
         img = nb.Nifti1Image(stddevimg, img.get_affine(), img.get_header())
-        nb.save(img,  self._gen_output_file_name('stddev'))
+        nb.save(img, self._gen_output_file_name('stddev'))
         return runtime
 
     def _list_outputs(self):