To provide a radio control clock having reduced or at least mitigated defects wherein an existing radio control clock is designed to be used in a specific country and cannot be used in different countries.

This radio control clock comprises a main unit 200 and three antenna modules 300 having mutual interchangeability. The main unit 200 is equipped with an operation circuit and a contact part. The operation circuit has a CPU and three decoders connected to the circuit for decoding an RF time signal having a different conveyance frequency and received by the modules 300, and the decoders are connected to the contact part. Each module 300 has a body 310 connectable to a main unit body 210, an operation circuit and a contact part connectable to the contact part 240 when the module 300 is connected to the main unit 200. The operation circuit has a receiver modulated so as to receive the RF time signal in a specific conveyance frequency broadcasting in a specific country, and to transmit the received signal to a pertinent decoder via the contact part so that the local time can be displayed on a display 217 by the CPU.