diff --git a/cmd/oras/internal/meta/pull.go b/cmd/oras/internal/meta/pull.go
index f4a91374f..7b28ba29a 100644
--- a/cmd/oras/internal/meta/pull.go
+++ b/cmd/oras/internal/meta/pull.go
@@ -48,7 +48,7 @@ type pull struct {
 func NewPull(digestReference string, files []File) pull {
 	return pull{
 		DigestReference: DigestReference{
-			Reference: digestReference,
+			Ref: digestReference,
 		},
 		Files: files,
 	}
diff --git a/cmd/oras/internal/meta/type.go b/cmd/oras/internal/meta/type.go
index 58262208e..c2999d2b7 100644
--- a/cmd/oras/internal/meta/type.go
+++ b/cmd/oras/internal/meta/type.go
@@ -22,13 +22,13 @@ import (
 
 // DigestReference is a reference to an artifact with digest.
 type DigestReference struct {
-	Reference string `json:"Ref"`
+	Ref string `json:"Ref"`
 }
 
 // ToDigestReference converts a name and digest to a digest reference.
 func ToDigestReference(name string, digest string) DigestReference {
 	return DigestReference{
-		Reference: name + "@" + digest,
+		Ref: name + "@" + digest,
 	}
 }