diff --git a/django/db/backends/sqlite3/base.py b/django/db/backends/sqlite3/base.py
index 8ddb736d89..1ed4a95e79 100644
--- a/django/db/backends/sqlite3/base.py
+++ b/django/db/backends/sqlite3/base.py
@@ -7,6 +7,7 @@ Python 2.5 and later can use a pysqlite2 module or the sqlite3 module in the
 standard library.
 """
 
+import re
 import sys
 
 from django.db import utils
@@ -185,6 +186,8 @@ class DatabaseWrapper(BaseDatabaseWrapper):
         if self.settings_dict['NAME'] != ":memory:":
             BaseDatabaseWrapper.close(self)
 
+FORMAT_QMARK_REGEX = re.compile(r'(?![^%])%s')
+
 class SQLiteCursorWrapper(Database.Cursor):
     """
     Django uses "format" style placeholders, but pysqlite2 uses "qmark" style.
@@ -192,8 +195,8 @@ class SQLiteCursorWrapper(Database.Cursor):
     you'll need to use "%%s".
     """
     def execute(self, query, params=()):
+        query = self.convert_query(query)
         try:
-            query = self.convert_query(query, len(params))
             return Database.Cursor.execute(self, query, params)
         except Database.IntegrityError, e:
             raise utils.IntegrityError, utils.IntegrityError(*tuple(e)), sys.exc_info()[2]
@@ -201,19 +204,16 @@ class SQLiteCursorWrapper(Database.Cursor):
             raise utils.DatabaseError, utils.DatabaseError(*tuple(e)), sys.exc_info()[2]
 
     def executemany(self, query, param_list):
+        query = self.convert_query(query)
         try:
-            query = self.convert_query(query, len(param_list[0]))
             return Database.Cursor.executemany(self, query, param_list)
-        except (IndexError,TypeError):
-            # No parameter list provided
-            return None
         except Database.IntegrityError, e:
             raise utils.IntegrityError, utils.IntegrityError(*tuple(e)), sys.exc_info()[2]
         except Database.DatabaseError, e:
             raise utils.DatabaseError, utils.DatabaseError(*tuple(e)), sys.exc_info()[2]
 
-    def convert_query(self, query, num_params):
-        return query % tuple("?" * num_params)
+    def convert_query(self, query):
+        return FORMAT_QMARK_REGEX.sub('?', query).replace('%%','%')
 
 def _sqlite_extract(lookup_type, dt):
     if dt is None:
diff --git a/tests/regressiontests/backends/tests.py b/tests/regressiontests/backends/tests.py
index b31f35a44e..7a0038a286 100644
--- a/tests/regressiontests/backends/tests.py
+++ b/tests/regressiontests/backends/tests.py
@@ -66,6 +66,19 @@ class DateQuotingTest(TestCase):
         classes = models.SchoolClass.objects.filter(last_updated__day=20)
         self.assertEqual(len(classes), 1)
 
+class ParameterHandlingTest(TestCase):
+    def test_bad_parameter_count(self):
+        "An executemany call with too many/not enough parameters will raise an exception (Refs #12612)"
+        cursor = connection.cursor()
+        query = ('INSERT INTO %s (%s, %s) VALUES (%%s, %%s)' % (
+            connection.introspection.table_name_converter('backends_square'),
+            connection.ops.quote_name('root'),
+            connection.ops.quote_name('square')
+        ))
+        self.assertRaises(Exception, cursor.executemany, query, [(1,2,3),])
+        self.assertRaises(Exception, cursor.executemany, query, [(1,),])
+
+
 def connection_created_test(sender, **kwargs):
     print 'connection_created signal'