The fuel temperature of the reactor can affect the Doppler effect, which in turn affects the reactivity of the core. It is an important factor that affects and controls the reactivity of the reactor, and is also a key parameter for evaluating whether the core has melted. At present, in the nuclear industry, the fuel thermal conductivity equation is mainly numerically discretized to obtain the fuel temperature distribution, and weighted to obtain the fuel Doppler temperature. In the solving process, the fuel temperature is coupled with the material properties, which has a strong nonlinear effect. In order to gain a clearer understanding of the thermal conductivity model of pressurized water reactor (PWR) fuel rods and evaluate which parameters are the main factors affecting key outcome parameters such as the maximum fuel temperature, the sensitivity analysis (SA) on the fuel temperature numerical calculation model for three large advanced pressurized water reactors was conducted in the paper. The results show that: (1) the sensitivity analysis results for the HPR1000 and other two pressurized water reactors using the same method are consistent, and the key input parameters and ranking that affect the calculation results obtained by the two sensitivity analysis methods are consistent. (2) The power, inlet coolant temperature, the second coefficient of fuel Thermal conductivity, fuel pellet radius, the first coefficient of fuel Thermal conductivity and gap heat transfer coefficient have a significant impact on the fuel maximum temperature. The inlet coolant temperature, power, Doppler temperature weighting coefficient, fuel pellet radius, the second coefficient of fuel Thermal conductivity and gap heat transfer coefficient have a significant impact on the fuel Doppler temperature. The inlet coolant temperature of the coolant has the greatest impact on the outlet enthalpy. The inlet coolant temperature and pressure of the coolant have a significant impact on the outlet steam quality.