The invention provides a fuel cooling device used for a vehicle. The fuel cooling device used for the vehicle is provided with a return passage and a fuel cooling part. Residual fuel, which is not sprayed, in the fuel supplied to a fuel sprayer valve is returned to a fuel tank as return fuel through the return passage. The fuel cooling part is arranged on the return passage, a part of refrigerant of an air conditioner of the vehicle is circulated to the fuel cooling part, and the return fuel carries out heat exchange with the refrigerant flowing through the fuel cooling part to cool the return fuel. When the fuel cooling device of the vehicle enables part of the refrigerant to circulate to the fuel cooling part in order to cool the return fuel, the driving quantity of a compressor is larger than that of the compressor when the return fuel is not cooled.