The thermal management of the key parts of fuel cell vehicles is very important for the stable operation, but the influence of variable driving conditions on the temperature of the key parts of the vehicles is not clear. This paper analyzes the composition of the thermal management system of fuel cell vehicles and the thermal management strategies commonly used at present, and takes a fuel cell passenger car as an example to study the influence of China light-duty vehicle test cycle(CLTC-P), low-speed climbing condition and high-speed climbing condition on the temperature of the key parts of the vehicle. The results show that the temperature difference of different parts of the vehicle in CLTC-P is not obvious, however the temperature difference of different parts of the vehicle in low speed climbing and high speed climbing is larger than that in CLTC-P.