PURPOSE: To improve the service function with simple constitution by detecting key depression information of a ten-key for dialing depressed by a subscriber at the start of power supply from an exchange, storing the information and applying communication control of information with the exchange with the key depression information.

CONSTITUTION: A dialing ten-key 328 is used as an input means and key depression information of the dialing ten-key 328 depressed for power supply start to a telephone set 3a is stored in a key information memory to set the operation. Thus, other input means such as the switch for the setting is not required to be provided and the telephone set whose service function is improved is attained with simple constitution. Then lots of kinds of tone colors of a tone ringer 325 are set freely by a subscriber without provision of a special hardware.