In a charge control device installable in a motor vehicle and designed to execute charge control for a battery based on an output power of a power generator, a nonvolatile memory stores therein data required to execute the charge control for the battery. A communication circuit is communicably connectable to first and second devices different from each other. The first device allows entrance of information required to rewrite the data stored in the nonvolatile memory. A rewriting unit rewrites the data stored in the nonvolatile memory based on the entered information only when the first device is communicably connected to the communication circuit.