A charge control system including a solar panel configured to generate electric power with sunlight, a chargeable and dischargeable first battery, a chargeable and dischargeable second battery, and a charge control unit connected to the solar panel, the first battery and the second battery, and a method of the charge control system are provided. The charge control unit is configured to switch between a first mode (indirect charge mode) in which a process of charging the first battery with electric power generated by the solar panel and a process of charging the second battery with electric power stored in the first battery are repeatedly executed depending on a state of charge of the first battery and a second mode (direct charge mode) in which electric power generated by the solar panel is directly charged into the second battery based on at least electric power generated by the solar panel.