This paper reports that the(2+1)resonance enhanced multi-photon ionization spectra of SH radical in exteal fields are simulated using the split-operator scheme of time-dependent wave-packet method.Two ionic states.i.e.α1△ and b1∑+,are involved in the simulation.It gives the simulated photoelectron spectra,the population in each electronic state,as well as the projection of the wave-packet in each electronic state on different vibrational states.These results show that the so-called four-state model can represent the experimental results well.