diff --git a/etcdctl/README.md b/etcdctl/README.md
index db273ec83..990a3fdcd 100644
--- a/etcdctl/README.md
+++ b/etcdctl/README.md
@@ -913,7 +913,7 @@ If NOSPACE alarm is present:
 
 ### DEFRAG [options]
 
-DEFRAG defragments the backend database file for a set of given endpoints while etcd is running, ~~or directly defragments an etcd data directory while etcd is not running~~. When an etcd member reclaims storage space from deleted and compacted keys, the space is kept in a free list and the database file remains the same size. By defragmenting the database, the etcd member releases this free space back to the file system.
+DEFRAG defragments the backend database file for a set of given endpoints while etcd is running. When an etcd member reclaims storage space from deleted and compacted keys, the space is kept in a free list and the database file remains the same size. By defragmenting the database, the etcd member releases this free space back to the file system.
 
 **Note: to defragment offline (`--data-dir` flag), use: `etcutl defrag` instead**
 
@@ -921,9 +921,6 @@ DEFRAG defragments the backend database file for a set of given endpoints while
 
 **Note that defragmentation request does not get replicated over cluster. That is, the request is only applied to the local node. Specify all members in `--endpoints` flag or `--cluster` flag to automatically find all cluster members.**
 
-#### Options
-
-- data-dir -- Optional. **Deprecated**. If present, defragments a data directory not in use by etcd. To be removed in v3.6.
 
 #### Output
 
@@ -946,16 +943,6 @@ Finished defragmenting etcd member[http://127.0.0.1:22379]
 Finished defragmenting etcd member[http://127.0.0.1:32379]
 ```
 
-To defragment a data directory directly, use the `etcdutl` with `--data-dir` flag 
-(`etcdctl` will remove this flag in v3.6):
-
-``` bash
-# Defragment while etcd is not running
-./etcdutl defrag --data-dir default.etcd
-# success (exit status 0)
-# Error: cannot open database at default.etcd/member/snap/db
-```
-
 #### Remarks
 
 DEFRAG returns a zero exit code only if it succeeded defragmenting all given endpoints.
diff --git a/etcdctl/ctlv3/command/defrag_command.go b/etcdctl/ctlv3/command/defrag_command.go
index 9b4f29a6a..5ebf4483d 100644
--- a/etcdctl/ctlv3/command/defrag_command.go
+++ b/etcdctl/ctlv3/command/defrag_command.go
@@ -20,14 +20,9 @@ import (
 	"time"
 
 	"github.com/spf13/cobra"
-	"go.etcd.io/etcd/etcdutl/v3/etcdutl"
 	"go.etcd.io/etcd/pkg/v3/cobrautl"
 )
 
-var (
-	defragDataDir string
-)
-
 // NewDefragCommand returns the cobra command for "Defrag".
 func NewDefragCommand() *cobra.Command {
 	cmd := &cobra.Command{
@@ -36,19 +31,10 @@ func NewDefragCommand() *cobra.Command {
 		Run:   defragCommandFunc,
 	}
 	cmd.PersistentFlags().BoolVar(&epClusterEndpoints, "cluster", false, "use all endpoints from the cluster member list")
-	cmd.Flags().StringVar(&defragDataDir, "data-dir", "", "Optional. If present, defragments a data directory not in use by etcd.")
-	cmd.MarkFlagDirname("data-dir")
 	return cmd
 }
 
 func defragCommandFunc(cmd *cobra.Command, args []string) {
-	if len(defragDataDir) > 0 {
-		fmt.Fprintf(os.Stderr, "Use `etcdutl defrag` instead. The --data-dir is going to be decomissioned in v3.6.\n\n")
-		err := etcdutl.DefragData(defragDataDir)
-		if err != nil {
-			cobrautl.ExitWithError(cobrautl.ExitError, err)
-		}
-	}
 
 	failures := 0
 	c := mustClientFromCmd(cmd)
diff --git a/tests/e2e/ctl_v3_defrag_test.go b/tests/e2e/ctl_v3_defrag_test.go
index 6abf855f4..c47ed3f4c 100644
--- a/tests/e2e/ctl_v3_defrag_test.go
+++ b/tests/e2e/ctl_v3_defrag_test.go
@@ -22,9 +22,6 @@ import (
 
 func TestCtlV3DefragOnline(t *testing.T) { testCtl(t, defragOnlineTest) }
 
-func TestCtlV3DefragOffline(t *testing.T) {
-	testCtlWithOffline(t, maintenanceInitKeys, defragOfflineTest)
-}
 func TestCtlV3DefragOfflineEtcdutl(t *testing.T) {
 	testCtlWithOffline(t, maintenanceInitKeys, defragOfflineTest, withEtcdutl())
 }