Abstract: Nowadays, many countries start to develop advanced UO₂ composite fuel pellet that can be used in the pressurized water reactor (PWR) by adding a few amounts of the second phase materials with high thermal conducting. In this paper, the influences of key structural parameters on the thermal conducting properties of advanced UO₂ composite fuel pellet were investigated by finite element analysis method. The results show that a few amounts of the second phase materials can reduce the center line temperature of the fuel pellets significantly. The type, amount and distribution form of the second phase have important influence on the thermal conducting property of advanced UO₂ composite fuel pellet.