diff --git a/pkg/expansion/system.go b/pkg/expansion/system.go
index 5287b159726..82b59c8c187 100644
--- a/pkg/expansion/system.go
+++ b/pkg/expansion/system.go
@@ -85,6 +85,9 @@ func ValidateTemplate(template *expansionunversioned.ExpansionTemplate) error {
 	if k == "" {
 		return fmt.Errorf("ExpansionTemplate has empty name field")
 	}
+	if len(k) > 64 {
+		return fmt.Errorf("ExpansionTemplate name must be less than 64 characters")
+	}
 	if template.Spec.TemplateSource == "" {
 		return fmt.Errorf("ExpansionTemplate %s has empty source field", k)
 	}
diff --git a/pkg/expansion/system_test.go b/pkg/expansion/system_test.go
index 9eaf394b6e6..726c915e3d1 100644
--- a/pkg/expansion/system_test.go
+++ b/pkg/expansion/system_test.go
@@ -336,6 +336,24 @@ func TestValidateTemplate(t *testing.T) {
 			}),
 			errFn: matchErr("empty name"),
 		},
+		{
+			name: "name too long",
+			temp: *fixtures.NewTemplate(&fixtures.TemplateData{
+				Name: "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+				Apply: []match.ApplyTo{{
+					Groups:   []string{"apps"},
+					Kinds:    []string{"Deployment"},
+					Versions: []string{"v1"},
+				}},
+				Source: "spec.template",
+				GenGVK: expansionunversioned.GeneratedGVK{
+					Group:   "",
+					Version: "v1",
+					Kind:    "Pod",
+				},
+			}),
+			errFn: matchErr("less than 64"),
+		},
 		{
 			name: "missing source",
 			temp: *fixtures.NewTemplate(&fixtures.TemplateData{