Abstract: The philosophy of time-marching method is firstly applied to through-flow computation.The governing equation is solved with four step Runge-Kutta scheme.In result,the difficulty in the transonic highly-loaded turbomachinery designing,is surmounted.As an example,an axial supersonic inflow shock rotor is designed,with a fine grid,a strong shock is found in flow path.It is indicated that the time-marching method is suitable for through-flow calculation,especially for turbomachinery,whose flow velocity axial component is transonic.