diff --git a/git.go b/git.go
index e5fe812..b20f993 100644
--- a/git.go
+++ b/git.go
@@ -88,7 +88,7 @@ func (oid *Oid) Equal(oid2 *Oid) bool {
 
 func (oid *Oid) IsZero() bool {
 	for _, a := range oid {
-		if a != '0' {
+		if a != 0 {
 			return false
 		}
 	}
diff --git a/git_test.go b/git_test.go
index fff3c6c..6542ca0 100644
--- a/git_test.go
+++ b/git_test.go
@@ -54,3 +54,11 @@ func seedTestRepo(t *testing.T, repo *Repository) (*Oid, *Oid) {
 
 	return commitId, treeId
 }
+
+func TestOidZero(t *testing.T) {
+	var zeroId Oid
+
+	if !zeroId.IsZero() {
+		t.Error("Zero Oid is not zero")
+	}
+}