diff --git a/moto/cognitoidp/responses.py b/moto/cognitoidp/responses.py
index f3c005ff..78725bcf 100644
--- a/moto/cognitoidp/responses.py
+++ b/moto/cognitoidp/responses.py
@@ -287,7 +287,7 @@ class CognitoIdpResponse(BaseResponse):
             user_pool_id, limit=limit, pagination_token=token
         )
         if filt:
-            name, value = filt.replace('"', "").split("=")
+            name, value = filt.replace('"', "").replace(" ", "").split("=")
             users = [
                 user
                 for user in users
diff --git a/tests/test_cognitoidp/test_cognitoidp.py b/tests/test_cognitoidp/test_cognitoidp.py
index 65c5151e..06dae995 100644
--- a/tests/test_cognitoidp/test_cognitoidp.py
+++ b/tests/test_cognitoidp/test_cognitoidp.py
@@ -1085,6 +1085,13 @@ def test_list_users():
     result["Users"].should.have.length_of(1)
     result["Users"][0]["Username"].should.equal(username_bis)
 
+    # checking Filter with space
+    result = conn.list_users(
+        UserPoolId=user_pool_id, Filter='phone_number = "+33666666666'
+    )
+    result["Users"].should.have.length_of(1)
+    result["Users"][0]["Username"].should.equal(username_bis)
+
 
 @mock_cognitoidp
 def test_list_users_returns_limit_items():