Abstract: Ｔhe equations of onedimensional threetemperature radiation magnetohydrodynamics, which are to describe the plasma process of Zpinch, were set up under Largrangian coordinates. The Al wirearray Z-pinch experiment on Saturn in Sandia laboratory in USA, was simulated using our onedimensional lagrangian code based on the equations. The reasonable and selfconsistent spatiotemporal distributions of all plasma parameters in the process were obtained. The time and velocity of Zpinch plasma to center, pulse width and energy of Xray radiated by the Zpinch plasma are basically agreed with the experimental results on Saturn. The results suggested that the equations and its code are correct.