diff --git a/test/api/test_tools.py b/test/api/test_tools.py
index cd0a8026fdd..6d02738796c 100644
--- a/test/api/test_tools.py
+++ b/test/api/test_tools.py
@@ -106,6 +106,20 @@ class ToolsTestCase( api.ApiTestCase ):
         output1_content = self.dataset_populator.get_history_dataset_content( history_id, dataset=output )
         assert output1_content == "--ex1,ex2"
 
+    @skip_without_tool( "multi_select" )
+    def test_multi_select_optional( self ):
+        history_id = self.dataset_populator.new_history()
+        inputs = {
+            "select_ex": ["--ex1"],
+            "select_optional": None,
+        }
+        response = self._run( "multi_select", history_id, inputs, assert_ok=True )
+        output = response[ "outputs" ]
+        output1_content = self.dataset_populator.get_history_dataset_content( history_id, dataset=output[ 0 ] )
+        output2_content = self.dataset_populator.get_history_dataset_content( history_id, dataset=output[ 1 ] )
+        assert output1_content.strip() == "--ex1"
+        assert output2_content.strip() == "None", output2_content
+
     @skip_without_tool( "multi_data_param" )
     def test_multidata_param( self ):
         history_id = self.dataset_populator.new_history()
diff --git a/test/functional/tools/multi_select.xml b/test/functional/tools/multi_select.xml
index d1356157cae..5f940609e94 100644
--- a/test/functional/tools/multi_select.xml
+++ b/test/functional/tools/multi_select.xml
@@ -3,7 +3,7 @@
   <configfiles>
     <configfile name="config">${select_ex}</configfile>
   </configfiles>
-  <command>cat $config > $output</command>
+  <command>cat $config > $output; echo '$select_optional' > $output2</command>
   <inputs>
     <param name="select_ex" type="select" display="checkboxes" multiple="true">
       <option value="--ex1">Ex1</option>
@@ -12,9 +12,17 @@
       <option value="--ex4">Ex4</option>
       <option value="ex5">Ex5</option>
     </param>
+    <param name="select_optional" type="select" optional="true">
+      <option value="--ex1">Ex1</option>
+      <option value="ex2">Ex2</option>
+      <option value="--ex3">Ex3</option>
+      <option value="--ex4">Ex4</option>
+      <option value="ex5">Ex5</option>
+    </param>
   </inputs>
   <outputs>
     <data format="txt" name="output" />
+    <data format="txt" name="output2" />    
   </outputs>
   <tests>
     <test>