diff --git a/cmd/common-main.go b/cmd/common-main.go
index 70ce27c41..9719c9846 100644
--- a/cmd/common-main.go
+++ b/cmd/common-main.go
@@ -22,7 +22,6 @@ import (
 	"crypto/tls"
 	"crypto/x509"
 	"encoding/gob"
-	"encoding/hex"
 	"errors"
 	"fmt"
 	"math/rand"
@@ -339,8 +338,6 @@ func handleCommonEnvVars() {
 	switch {
 	case env.IsSet(config.EnvKMSSecretKey) && env.IsSet(config.EnvKESEndpoint):
 		logger.Fatal(errors.New("ambigious KMS configuration"), fmt.Sprintf("The environment contains %q as well as %q", config.EnvKMSSecretKey, config.EnvKESEndpoint))
-	case env.IsSet(config.EnvKMSMasterKey) && env.IsSet(config.EnvKESEndpoint):
-		logger.Fatal(errors.New("ambigious KMS configuration"), fmt.Sprintf("The environment contains %q as well as %q", config.EnvKMSMasterKey, config.EnvKESEndpoint))
 	}
 
 	if env.IsSet(config.EnvKMSSecretKey) {
@@ -348,21 +345,6 @@ func handleCommonEnvVars() {
 		if err != nil {
 			logger.Fatal(err, "Unable to parse the KMS secret key inherited from the shell environment")
 		}
-	} else if env.IsSet(config.EnvKMSMasterKey) {
-		// FIXME: remove this block by June 2021
-		logger.LogIf(GlobalContext, fmt.Errorf("legacy KMS configuration, this environment variable %q is deprecated and will be removed by June 2021", config.EnvKMSMasterKey))
-		v := strings.SplitN(env.Get(config.EnvKMSMasterKey, ""), ":", 2)
-		if len(v) != 2 {
-			logger.Fatal(errors.New("invalid "+config.EnvKMSMasterKey), "Unable to parse the KMS secret key inherited from the shell environment")
-		}
-		secretKey, err := hex.DecodeString(v[1])
-		if err != nil {
-			logger.Fatal(err, "Unable to parse the KMS secret key inherited from the shell environment")
-		}
-		GlobalKMS, err = kms.New(v[0], secretKey)
-		if err != nil {
-			logger.Fatal(err, "Unable to parse the KMS secret key inherited from the shell environment")
-		}
 	}
 	if env.IsSet(config.EnvKESEndpoint) {
 		var endpoints []string
diff --git a/dockerscripts/docker-entrypoint.sh b/dockerscripts/docker-entrypoint.sh
index f2a26b64d..63ac45cb2 100755
--- a/dockerscripts/docker-entrypoint.sh
+++ b/dockerscripts/docker-entrypoint.sh
@@ -71,17 +71,6 @@ docker_kms_secret_encryption_env() {
     fi
 }
 
-## Legacy
-## Set KMS_MASTER_KEY from docker secrets if provided
-docker_kms_master_encryption_env() {
-    KMS_MASTER_KEY_FILE="/run/secrets/$MINIO_KMS_MASTER_KEY_FILE"
-
-    if [ -f "$KMS_MASTER_KEY_FILE" ]; then
-        MINIO_KMS_MASTER_KEY="$(cat "$KMS_MASTER_KEY_FILE")"
-        export MINIO_KMS_MASTER_KEY
-    fi
-}
-
 # su-exec to requested user, if service cannot run exec will fail.
 docker_switch_user() {
     if [ ! -z "${MINIO_USERNAME}" ] && [ ! -z "${MINIO_GROUPNAME}" ]; then
diff --git a/internal/config/constants.go b/internal/config/constants.go
index c792559f8..911d256ee 100644
--- a/internal/config/constants.go
+++ b/internal/config/constants.go
@@ -41,7 +41,6 @@ const (
 
 	EnvUpdate = "MINIO_UPDATE"
 
-	EnvKMSMasterKey  = "MINIO_KMS_MASTER_KEY" // legacy
 	EnvKMSSecretKey  = "MINIO_KMS_SECRET_KEY"
 	EnvKESEndpoint   = "MINIO_KMS_KES_ENDPOINT"
 	EnvKESKeyName    = "MINIO_KMS_KES_KEY_NAME"