Open your device's Settings menu .
Under "Device," touch Sound & notification.
Under "Notification," touch When device is locked. You can choose from the following settings:
Show all notification content: You'll get all notifications on the lock screen, except for apps that you designate as having sensitive notifications in the "App notifications" setting menu. When you have this setting turned on, keep in mind that all content (including contents of incoming emails and chats) will be visible on your lock screen.
Hide sensitive notification content: You'll get notifications on the lock screen but the content won't be available or it will say "Contents hidden" for notifications that you designate as sensitive. For example, you'll get a notification for an incoming email or chat, but the contents won't be visible on your lock screen. You need to have a screen lock other than the "Slide" option set up (like a pin, pattern, or password) to see this as a notification option.
Don't show notifications at all: You won't get any notifications on the lock screen.