Disclosed are a communication apparatus capable of registering telephone directory data at once from e-mail containing the telephone directory data into a telephone directory of a communication apparatus. A communication apparatus according to this invention is a communication apparatus having a function of transmitting/receiving e-mail, and characterized by including a communication partner information storage unit for storing communication partner information having predetermined registration items, an identifier detecting unit for detecting a predetermined identifier from received e-mail, and a registering unit for registering information described in the e-mail in accordance with the detected identifier into that registration item of the communication partner information which corresponds to the identifier.