diff --git a/changelogs/unreleased/9554-testsabirweb b/changelogs/unreleased/9554-testsabirweb
new file mode 100644
index 000000000..18b925797
--- /dev/null
+++ b/changelogs/unreleased/9554-testsabirweb
@@ -0,0 +1 @@
+Issue #9544: Add test coverage for S3 bucket name in MRAP ARN notation and fix bucket validation to accept ARN format
\ No newline at end of file
diff --git a/pkg/persistence/object_store.go b/pkg/persistence/object_store.go
index eaf983819..fd441e943 100644
--- a/pkg/persistence/object_store.go
+++ b/pkg/persistence/object_store.go
@@ -149,7 +149,8 @@ func (b *objectBackupStoreGetter) Get(location *velerov1api.BackupStorageLocatio
 	// if there are any slashes in the middle of 'bucket', the user
 	// probably put <bucket>/<prefix> in the bucket field, which we
 	// don't support.
-	if strings.Contains(bucket, "/") {
+	// Exception: MRAP ARNs (arn:aws:s3::...) legitimately contain slashes.
+	if strings.Contains(bucket, "/") && !strings.HasPrefix(bucket, "arn:aws:s3:") {
 		return nil, errors.Errorf("backup storage location's bucket name %q must not contain a '/' (if using a prefix, put it in the 'Prefix' field instead)", location.Spec.ObjectStorage.Bucket)
 	}
 
diff --git a/pkg/persistence/object_store_test.go b/pkg/persistence/object_store_test.go
index fac2f8d97..e9a3bde36 100644
--- a/pkg/persistence/object_store_test.go
+++ b/pkg/persistence/object_store_test.go
@@ -943,6 +943,24 @@ func TestNewObjectBackupStoreGetter(t *testing.T) {
 			wantBucket:    "bucket",
 			wantPrefix:    "prefix/",
 		},
+		{
+			name:     "when the Bucket field is an MRAP ARN, it should be valid",
+			location: builder.ForBackupStorageLocation("", "").Provider("provider-1").Bucket("arn:aws:s3::123456789012:accesspoint/abcdef0123456.mrap").Result(),
+			objectStoreGetter: objectStoreGetter{
+				"provider-1": newInMemoryObjectStore("arn:aws:s3::123456789012:accesspoint/abcdef0123456.mrap"),
+			},
+			credFileStore: velerotest.NewFakeCredentialsFileStore("", nil),
+			wantBucket:    "arn:aws:s3::123456789012:accesspoint/abcdef0123456.mrap",
+		},
+		{
+			name:     "when the Bucket field is an MRAP ARN with trailing slash, it should be valid and trimmed",
+			location: builder.ForBackupStorageLocation("", "").Provider("provider-1").Bucket("arn:aws:s3::123456789012:accesspoint/abcdef0123456.mrap/").Result(),
+			objectStoreGetter: objectStoreGetter{
+				"provider-1": newInMemoryObjectStore("arn:aws:s3::123456789012:accesspoint/abcdef0123456.mrap"),
+			},
+			credFileStore: velerotest.NewFakeCredentialsFileStore("", nil),
+			wantBucket:    "arn:aws:s3::123456789012:accesspoint/abcdef0123456.mrap",
+		},
 	}
 
 	for _, tc := range tests {