diff --git a/scrapy/http/request/form.py b/scrapy/http/request/form.py
index 1920cefe1..a12a2fd07 100644
--- a/scrapy/http/request/form.py
+++ b/scrapy/http/request/form.py
@@ -159,7 +159,7 @@ def _get_clickable(clickdata, form):
     # If we don't have clickdata, we just use the first clickable element
     if clickdata is None:
         el = clickables[0]
-        return (el.get('name'), el.get('value'))
+        return (el.get('name'), el.get('value') or '')
 
     # If clickdata is given, we compare it to the clickable elements to find a
     # match. We first look to see if the number is specified in clickdata,
@@ -171,7 +171,7 @@ def _get_clickable(clickdata, form):
         except IndexError:
             pass
         else:
-            return (el.get('name'), el.get('value'))
+            return (el.get('name'), el.get('value') or '')
 
     # We didn't find it, so now we build an XPath expression out of the other
     # arguments, because they can be used as such
@@ -179,7 +179,7 @@ def _get_clickable(clickdata, form):
             u''.join(u'[@%s="%s"]' % c for c in six.iteritems(clickdata))
     el = form.xpath(xpath)
     if len(el) == 1:
-        return (el[0].get('name'), el[0].get('value'))
+        return (el[0].get('name'), el[0].get('value') or '')
     elif len(el) > 1:
         raise ValueError("Multiple elements found (%r) matching the criteria "
                          "in clickdata: %r" % (el, clickdata))
diff --git a/tests/test_http_request.py b/tests/test_http_request.py
index b87045325..ff0941961 100644
--- a/tests/test_http_request.py
+++ b/tests/test_http_request.py
@@ -767,6 +767,40 @@ class FormRequestTest(RequestTest):
         self.assertEqual(fs[b'test2'], [b'val2'])
         self.assertEqual(fs[b'button1'], [b'submit1'])
 
+    def test_from_response_submit_novalue(self):
+        response = _buildresponse(
+            """<form action="post.php" method="POST">
+            <input type="hidden" name="test1" value="val1">
+            <input type="hidden" name="test2" value="val2">
+            <input type="submit" name="button1">Submit</button>
+            </form>""",
+            url="http://www.example.com/this/list.html")
+        req = self.request_class.from_response(response)
+        self.assertEqual(req.method, 'POST')
+        self.assertEqual(req.headers['Content-type'], b'application/x-www-form-urlencoded')
+        self.assertEqual(req.url, "http://www.example.com/this/post.php")
+        fs = _qs(req)
+        self.assertEqual(fs[b'test1'], [b'val1'])
+        self.assertEqual(fs[b'test2'], [b'val2'])
+        self.assertEqual(fs[b'button1'], [b''])
+
+    def test_from_response_button_novalue(self):
+        response = _buildresponse(
+            """<form action="post.php" method="POST">
+            <input type="hidden" name="test1" value="val1">
+            <input type="hidden" name="test2" value="val2">
+            <button type="submit" name="button1">Submit</button>
+            </form>""",
+            url="http://www.example.com/this/list.html")
+        req = self.request_class.from_response(response)
+        self.assertEqual(req.method, 'POST')
+        self.assertEqual(req.headers['Content-type'], b'application/x-www-form-urlencoded')
+        self.assertEqual(req.url, "http://www.example.com/this/post.php")
+        fs = _qs(req)
+        self.assertEqual(fs[b'test1'], [b'val1'])
+        self.assertEqual(fs[b'test2'], [b'val2'])
+        self.assertEqual(fs[b'button1'], [b''])
+
 def _buildresponse(body, **kwargs):
     kwargs.setdefault('body', body)
     kwargs.setdefault('url', 'http://example.com')