diff --git a/tests/fields/fields.py b/tests/fields/fields.py
index dbba6f9f..bf2b5dd5 100644
--- a/tests/fields/fields.py
+++ b/tests/fields/fields.py
@@ -1551,6 +1551,8 @@ class FieldTest(unittest.TestCase):
             name = StringField()
             preferences = EmbeddedDocumentField(PersonPreferences)
 
+        Person.drop_collection()
+
         person = Person(name='Test User')
         person.preferences = 'My Preferences'
         self.assertRaises(ValidationError, person.validate)
@@ -1583,6 +1585,8 @@ class FieldTest(unittest.TestCase):
             content = StringField()
             author = EmbeddedDocumentField(User)
 
+        BlogPost.drop_collection()
+
         post = BlogPost(content='What I did today...')
         post.author = PowerUser(name='Test User', power=47)
         post.save()