In order to improve the germination efficiency of Cassia mimosoides seed, the effects of concentrated sulfuric acid, sodium hydroxide, temperature and culture medium on seed germination and seedling growth of C. mimosoides were investigated. In this study, the seeds were immersed in water at different temperatures and sodium hydroxide with different concentrations for 10 min, and the seeds were immersed in concentrated sulfuric acid for different periods of time, and then inoculated on media, the effects of the three treatment methods on germination of seeds were studied. It was found that concentrated sulfuric acid and sodium hydroxide had no effect on seed germination of C. mimosoides. The seed expansion rate, germination rate and other indexes were enhanced with the increase of temperature of soaking water, and when the water temperature was 80°C, the best result of seed germination was gained in C. mimosoides. Compared with MS medium, seed inoculation on 1/2MS medium was more beneficial to the growth and development of germinated seedlings.