A fluid temperature control device, which is particularly suitably applied to the temperature control of a processing liquid in a semiconductor device manufacturing process, capable of performing quickly and precisely the temperature control of a temperature-controlled fluid, and the device can also be made as small as possible. This fluid temperature control device includes a body block having flow passage grooves formed therein; heat transfer plates which are disposed on surfaces of the body block to form flow passages where a temperature-controlled fluid flows; heaters which heat the temperature-controlled fluid flowing through the flow passages via at least one of the heat transfer plates; and thermoelectric modules which heat and cool the temperature-controlled fluid flowing through the flow passages via at least one of the heat transfer plates.