A flowfield simulation code was developed based on Reynolds-averaged Navier-Stokes equations and validated by experimental data.A numerical optimization code was developed and applied to the optimization design of a circumferentially curved transonic compressor rotor.Results indicate that the circumferential curving can effectively change the three dimensional shock wave structures and weaken wake losses.Optimized blades improve adiabatic efficiency approximately 0.59% and possess fine off-design performance.