diff --git a/models/repo.go b/models/repo.go
index ac9efaf7a1a3..672507819add 100644
--- a/models/repo.go
+++ b/models/repo.go
@@ -1520,6 +1520,18 @@ func DeleteRepository(doer *User, uid, repoID int64) error {
 		return err
 	}
 
+	// Dependencies for issues in this repository
+	if _, err = sess.In("issue_id", deleteCond).
+		Delete(&IssueDependency{}); err != nil {
+		return err
+	}
+
+	// Delete dependencies for issues in other repositories
+	if _, err = sess.In("dependency_id", deleteCond).
+		Delete(&IssueDependency{}); err != nil {
+		return err
+	}
+
 	if _, err = sess.In("issue_id", deleteCond).
 		Delete(&IssueUser{}); err != nil {
 		return err