According to one embodiment, a telephone exchange system includes a first telephone exchange apparatus, a second telephone exchange apparatus which is connected to the first telephone exchange apparatus via a first communication network, a computer apparatus which establishes a communication link with the first telephone exchange apparatus via the first communication network and executes a part of function regarding exchange processing by the first and the second telephone exchange apparatuses, a second communication network which connects among a plurality of telephone terminals and the first and the second telephone exchange apparatuses, a communicator which connects a telephone terminal of a request source to the first telephone exchange apparatus via the second communication network, and a controller which executes the service based on a communication result by the communicator.