Accident tolerant fuel is a new fuel concept which is proposed to improve the reactor’s ability to cope with severe accident conditions. The application of accident tolerant fuel would fundamentally improve the resistance of new nuclear power plants to serious accidents and effectively improve the safety of nuclear power. However, due to process limitations, the loading capacity of the accident tolerant fuel 235U is lower than that of AFA3G fuel. In order to meet the economic requirements of the nuclear power plant, the conceptual design of high uranium density pellet with 235U in the fuel rod being higher than that of AFA3G fuel is further introduced. The economic analysis of three different high uranium density pellet cases(UN pellet, U3Si2 pellets, 30vol%UN + UO2 composite pellets)under SiC cladding is carried out in this paper. It is verified that the full core loaded with high uranium density pellets can meet the economic requirements of the power plant while meeting the requirements of fuel management and refuelling design. The results show that the three kinds of high uranium density pellets all meet the economic requirements. The economy of U3Si2 pellets is better than that of UN pellets and 30vol%UN + UO2 composite pellets. The UN pellets and 30vol%UN + UO2 composite pellets basically meet the nuclear design requirements.