To see a mailman in your dream, symbolizes your communications with others. You need to get the word out about something. If the mailman does not have any mail for you, then it signifies disappointments in some aspect of your life.
If you are not a mailman in real life, but dream that you are one, suggests that a message is being channeled to you from your unconscious. Pay close attention to the message of this dream. Alternatively, it may mean that you have been entrusted with a special message or secret.