Comparative study of dissolved matter of chrysophanol of semen Cassia and the powder by supermicro-pulverization was made. In same extraction time only 7.6% chrysophanol in semen Cassia was extracted compared with in the groups of supermicro-pulverized powder of semen Cassia in which 69.7%

57.1% and 32.4% chrysophanol were extracted. The amount of dissolved matter of chrysophanol of supermicro-pulverized powder of semen Cassia by 5 minutes immersed in water was same compared with that of crude drug of semen Cassia by 90 minutes decocted. Proper desiccation of sample before supermicro-pulverization could increase dissolved matter of chrysophanol.