A communication system, mail push system and method of pushing mail are disclosed. The communication terminal may comprise a parameter acquisition unit for acquiring at least one parameter related to a user usage state; an information transmission unit for transmitting, to a data processing device at a network side, first information including the at least one parameter related to the user usage state, a mail reception unit for receiving a mail from a mail push device at the network side, wherein the mail is pushed by the mail push device according to a mail push indication message which is related to the first information and second information from a second communication terminal, and the second communication terminal is separated from the communication terminal. The communication terminal, the mail push system and the method thereof may automatically select the communication terminal to which the mail is pushed, according to a parameter related to the current user usage state.