diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index 260f345fff..9f2a234d23 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -2,6 +2,7 @@ import datetime
 import decimal
 import re
 import time
+import math
 
 import django.utils.copycompat as copy
 
@@ -882,6 +883,11 @@ class IntegerField(Field):
             return None
         return int(value)
 
+    def get_prep_lookup(self, lookup_type, value):
+        if lookup_type == 'gte' or lookup_type == 'lt':
+            value = math.ceil(value)
+        return super(IntegerField, self).get_prep_lookup(lookup_type, value)
+
     def get_internal_type(self):
         return "IntegerField"
 
diff --git a/tests/regressiontests/queries/models.py b/tests/regressiontests/queries/models.py
index 06c4524d9d..69d990eb7f 100644
--- a/tests/regressiontests/queries/models.py
+++ b/tests/regressiontests/queries/models.py
@@ -428,6 +428,45 @@ constraints.
 >>> Number.objects.filter(Q(num__gt=7) & Q(num__lt=12) | Q(num__lt=4))
 [<Number: 8>]
 
+Bug #12239
+Float was being rounded to integer on gte queries on integer field.  Tests
+show that gt, lt, gte, and lte work as desired.  Note that the fix changes
+get_prep_lookup for gte and lt queries only.
+>>> Number.objects.filter(num__gt=11.9)
+[<Number: 12>]
+>>> Number.objects.filter(num__gt=12)
+[]
+>>> Number.objects.filter(num__gt=12.0)
+[]
+>>> Number.objects.filter(num__gt=12.1)
+[]
+>>> Number.objects.filter(num__lt=12)
+[<Number: 4>, <Number: 8>]
+>>> Number.objects.filter(num__lt=12.0)
+[<Number: 4>, <Number: 8>]
+>>> Number.objects.filter(num__lt=12.1)
+[<Number: 4>, <Number: 8>, <Number: 12>]
+>>> Number.objects.filter(num__gte=11.9)
+[<Number: 12>]
+>>> Number.objects.filter(num__gte=12)
+[<Number: 12>]
+>>> Number.objects.filter(num__gte=12.0)
+[<Number: 12>]
+>>> Number.objects.filter(num__gte=12.1)
+[]
+>>> Number.objects.filter(num__gte=12.9)
+[]
+>>> Number.objects.filter(num__lte=11.9)
+[<Number: 4>, <Number: 8>]
+>>> Number.objects.filter(num__lte=12)
+[<Number: 4>, <Number: 8>, <Number: 12>]
+>>> Number.objects.filter(num__lte=12.0)
+[<Number: 4>, <Number: 8>, <Number: 12>]
+>>> Number.objects.filter(num__lte=12.1)
+[<Number: 4>, <Number: 8>, <Number: 12>]
+>>> Number.objects.filter(num__lte=12.9)
+[<Number: 4>, <Number: 8>, <Number: 12>]
+
 Bug #7872
 Another variation on the disjunctive filtering theme.