To reduce battery wastage, by not making a battery serve as a power source but making a temperature rise of hydraulic oil in a hydraulic device serve as a heat source, in a heating device for a battery type forklift truck.

Hydraulic oil generating a rise of temperature in operation of a cargo handling device in the battery type forklift truck is allowed to flow into an oil cooler 8 connected to be inserted between a control valve 7 and an oil tank 9, to be fed to a driver side by driving a blower 11. In this way, heating can be operated with no consumption of power of a battery.