We have compared the acute toxicity, sub-acute toxicity and in vitro and in vivo anti-tumor action of the rude drug, stir-fried with rice, and alkali-processed drugs of Mylabris phalerata before and after removing the head, feet and wings. The results indicate that the toxicity of the processed drugs is lower than that of the rude ones; the toxicity becomes higher without head, feet, and wings; and the alkali-processing method is better than stir-frying with rice recorded in the pharmacopeia.