If you dream of receiving the telegram, then such dream denotes to the message you will receive from your inner self. This telegram could change a lot of the important factors that are happening in your life at the moment, because it may find the solution or resolve the problem you were not able to solve before. If you were the one who sent the telegram to somebody else, then such dream shows the important things you are willing to tell others. Pay attention to the particular person you sent the telegram to.
Read more about dreaming of Telegram in other dream meanings interpretations.