The two-dimensional temperature of insulation layer of solid rocket motor with moving boundary condition was computed.Charred layer-pyrolysis surface-original material model was applied and temperature computation formulas were calculated by taking convection heat transfer between pyrolysis gas and charred layer as heat source.The complicated boundary conditions were transformed into equivalent convection heat transfer and equivalent heat flux.Triangle grid was produced by transfinite interpolation to quicken grid generation and improve the quality of grid.The calculation results show that the astringency and stability of finite element method is good in calculating the temperature of insulation layer of solid rocket motor.