diff --git a/cmd/oras/root/manifest/index/create_test.go b/cmd/oras/root/manifest/index/create_test.go
new file mode 100644
index 000000000..4b2d16f5d
--- /dev/null
+++ b/cmd/oras/root/manifest/index/create_test.go
@@ -0,0 +1,56 @@
+/*
+Copyright The ORAS Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package index
+
+import (
+	"reflect"
+	"testing"
+)
+
+func Test_parseAnnotations(t *testing.T) {
+	tests := []struct {
+		name            string
+		input           []string
+		annotations     map[string]string
+		wantErr         bool
+		wantAnnotations map[string]string
+	}{
+		{
+			name:            "valid input",
+			input:           []string{"a=b", "c=d", "e=f"},
+			annotations:     make(map[string]string),
+			wantErr:         false,
+			wantAnnotations: map[string]string{"a": "b", "c": "d", "e": "f"},
+		},
+		{
+			name:            "invalid input",
+			input:           []string{"c:d", "e=f"},
+			annotations:     make(map[string]string),
+			wantErr:         true,
+			wantAnnotations: map[string]string{},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if err := parseAnnotations(tt.input, tt.annotations); (err != nil) != tt.wantErr {
+				t.Errorf("parseAnnotations() error = %v, wantErr %v", err, tt.wantErr)
+			}
+			if !reflect.DeepEqual(tt.annotations, tt.wantAnnotations) {
+				t.Errorf("parseAnnotations() annotations = %v, want %v", tt.annotations, tt.wantAnnotations)
+			}
+		})
+	}
+}
diff --git a/test/e2e/suite/command/manifest_index.go b/test/e2e/suite/command/manifest_index.go
index 336e2bae5..e90a8f2ed 100644
--- a/test/e2e/suite/command/manifest_index.go
+++ b/test/e2e/suite/command/manifest_index.go
@@ -172,6 +172,14 @@ var _ = Describe("1.1 registry users:", func() {
 				"does-not-exist").ExpectFailure().
 				MatchErrKeyWords("Error", "could not find", "does-not-exist").Exec()
 		})
+
+		It("should fail if given annotation input of wrong format", func() {
+			testRepo := indexTestRepo("create", "bad-annotations")
+			CopyZOTRepo(ImageRepo, testRepo)
+			ORAS("manifest", "index", "create", RegistryRef(ZOTHost, testRepo, ""),
+				string(multi_arch.LinuxAMD64.Digest), "-a", "foo:bar").ExpectFailure().
+				MatchErrKeyWords("Error", "annotation value doesn't match the required format").Exec()
+		})
 	})
 
 	When("running `manifest index update`", func() {