diff --git a/moto/ec2/models.py b/moto/ec2/models.py
index 73df55897..f87853e07 100644
--- a/moto/ec2/models.py
+++ b/moto/ec2/models.py
@@ -604,6 +604,12 @@ class Ami(TaggedEC2Instance):
             return getattr(self,filter_name)
         elif filter_name == 'image-id':
             return self.id
+        elif filter_name == 'state':
+            return self.state
+        elif filter_name.startswith('tag:'):
+            tag_name = filter_name.replace('tag:', '', 1)
+            tags = dict((tag['key'], tag['value']) for tag in self.get_tags())
+            return tags.get(tag_name)
         else:
             ec2_backend.raise_not_implemented_error("The filter '{0}' for DescribeImages".format(filter_name))
 
diff --git a/tests/test_ec2/test_amis.py b/tests/test_ec2/test_amis.py
index 95fe9f920..49221cc96 100644
--- a/tests/test_ec2/test_amis.py
+++ b/tests/test_ec2/test_amis.py
@@ -132,6 +132,32 @@ def test_ami_filters():
     amis_by_id = conn.get_all_images(filters={'image-id': imageA.id})
     set([ami.id for ami in amis_by_id]).should.equal(set([imageA.id]))
 
+    amis_by_id = conn.get_all_images(filters={'state': 'available'})
+    set([ami.id for ami in amis_by_id]).should.equal(set([imageA.id, imageB.id]))
+
+
+@mock_ec2
+def test_ami_filtering_via_tag():
+    conn = boto.connect_vpc('the_key', 'the_secret')
+
+    reservationA = conn.run_instances('ami-1234abcd')
+    instanceA = reservationA.instances[0]
+    imageA_id = conn.create_image(instanceA.id, "test-ami-A", "this is a test ami")
+    imageA = conn.get_image(imageA_id)
+    imageA.add_tag("a key", "some value")
+
+    reservationB = conn.run_instances('ami-abcd1234')
+    instanceB = reservationB.instances[0]
+    imageB_id = conn.create_image(instanceB.id, "test-ami-B", "this is a test ami")
+    imageB = conn.get_image(imageB_id)
+    imageB.add_tag("another key", "some other value")
+
+    amis_by_tagA = conn.get_all_images(filters={'tag:a key': 'some value'})
+    set([ami.id for ami in amis_by_tagA]).should.equal(set([imageA.id]))
+
+    amis_by_tagB = conn.get_all_images(filters={'tag:another key': 'some other value'})
+    set([ami.id for ami in amis_by_tagB]).should.equal(set([imageB.id]))
+
 
 @mock_ec2
 def test_getting_missing_ami():