The stratiform cloud can be simulated with a one-dimensional model, duo to its uniform horizontal distribution of physical characters. In this paper, a bin category model including detailed microphysical processes has been used to simulate a precipitation of the stratiform cloud on 1 June 2007 in Jilin Province, China. The simulation results depict explicitly both the spectrums of water droplet, ice crystal, graupel, and snow and the vertical distribution of the water content. The comparison between the simulation results and the data observed by Doppler radar and the Particle Measurement System (PMS) indicates that different microphysical processes contribute differently to the forming of particle spectrum within three layers, i.e. ice layer, mixed layer, and warm layer. The results show that the seeding particles from the ice layer to the mixed layer are ice crystals with diameter D＞300 μm. Seeded from the mixed layer to the warm layer, both melting ice particles and water droplets with D＞100 μm could collect abundant cloud droplets in the warm layer, leading to an obvious increase of rain intensity in the warm layer. Meanwhile, some rain droplets can be produced by coalescing among small cloud particles in the warm layer. The contribution rates of the three layers to rain intensity are 3.5%、38.5% and 58% respectively. The rainfall intensity near the ground and the droplet spectrum width are considerably different when there is no mixed layer or warm layer, i.e., 0.475 mm/h and 920 μm for lack of the mixed layer, whereas 0.807 mm/h and 1500 μm without the warm layer. With the absence of ice layer, there is no big difference in both rainfall intensity and water droplet spectrum, and the simulation result is close to that with presence of all the three layers.