The invention provides a communication apparatus which includes a look-up table, a receiving/transmitting module, and a processing module. The processing module is electrically connected to the look-up table and the receiving/transmitting module respectively. The look-up table stores a plurality of controlling messages and first phone numbers. Each controlling message corresponds to one of the first phone numbers. The receiving/transmitting module receives an incoming call including a second phone number. The processing module determines if the second phone number matches one of the first phone numbers, and if yes, the processing module generates information on the basis of the controlling message corresponding to the matched first phone number, and according to the second phone number, transmits the information through the receiving/transmitting module.