A vaporized fuel processing apparatus includes a case and a heating unit removably attached to the case by a twist lock structure. The case has a tank port and a purge port and contains an adsorbent therein. The tank port communicates with a fuel tank. The purge port communicates with an internal combustion engine. The heating unit has an atmospheric port and a heater. The atmospheric port is open to the atmosphere. The heater is disposed between the atmospheric port and the adsorbent.