Abstract: two-dimensional Euler equation,combustion model and loss calculation methods were used to establish the numerical simulation model of engine.A body fitted coordinate system is used to adapt the complex geometry boundary.Unsteady Euler equation was solved by implicit high order Godunov scheme,which had the characteristic of shock capturing and good numerical stability.The data comparisons of calculation and design showed: the components simulation precision was higher than that of whole engine,the turbine simulation precision was higher than that of compressor;the analysis of meridional plane calculation results showed: Flow separation at the exit of centrifugal compressors and simplifications of combustion chamber holes had big influence on total performance parameter calculation results.