Provided is a mobile telephone easily associating ringing tones and an address book. A control unit implementing the mobile telephone includes an input unit accepting input of data, an instruction detecting unit detecting an instruction for executing an action specific to the mobile telephone based on the input data, a flag setting unit setting for each address a flag for discriminating an address to be assigned a ringing tone from an address not to be assigned the ringing tone, a ringing tone retrieving unit retrieving the ringing tones assignable to the address book, a registrant-by-registrant basis ringing tone assigning unit executing an operation for assigning the ringing tone to each address book based on an entered instruction and the result of the retrieval by the ringing tone retrieving unit, and an output unit writing the flag set by the flag setting unit in a storage unit.