There is provided a communication device including a first communication unit configured to communicate with a first device having a telephone function through a first network; a second communication unit configured to communicate with a second device having a function of reproducing sound, through a second network; a data storage unit configured to store an incoming message as sound data; a sound data transmission unit configured to transmit the sound data to the second device in response to a request from the second device; a reproduction recordation unit configured to register the sound data which has been transmitted to the second device, as reproduced sound data; a reproduction judgment unit configured to judge whether the sound data is registered as reproduced sound data; and a sound data information transmission unit configured to transmit sound data information concerning the sound data judged not to be registered as reproduced sound data.