Mylabris is the dried body of the chinese blister beetle. The species used in medicine are Mylabris phalerata and M. cichorii. In recent studies, it has been found that Mylabris possesses antitumor properties, increases the number of leukocytes, and has irritant effects on the urinary organs. The crude extracts of Mylabris have been noted for their highly irritant action and other traditional uses of Mylabris include treatment of poor local blood circulation. The active constituent of Mylabris is cantharidin. The chemical is notable for its vesicant properties, but with severe side effects such as nephrotoxicity. This experiment examined the effect of extracts and fractions, obtained from Mylabris phalerata Pall. on hair growth activity of the C57BL/6N mice after topical application to skin. First, we examined the effect of an extracts, obtained from the alcohol extracts of dried Mylabris phalerata Pall. on hair growth activity of the C57BL/6N mice after topical application to skin. Second, we examined on hair growth activity of the cantharidin fraction of Mylabris phalerata Pall. compared to the control and 1% minoxidil groups. Third, we investigated the number of hair follicle and mast cells after topical application of extracts of Mylabris phalerata Pall. to skin for 16 days. The results were as follows: Hair growth effect from the extracts of Mylabris phalerata Pall.(0.312%) was observed in 80% of mice whose hair had been removed in 13 days. Hair growth effect from the extract of Mylabris phalerata Pall.(0.312 and 0.625%) and 1% minoxidil group was observed in 100% of mice whose hair had been clipped in 20 days. Hair growth effect from the cantharidin fraction(0.5%) and water fraction(0.5%) of Mylabris phalerata Pall. was observed in 100% of mice whose hair had been clipped in 24 days. The hair growth effect on the cantharidin fraction(0.125%) was observed to be strong compared with the minoxidil(3%) group, commercial hair growth agents, in mice whose hair had been clipped in 19 days. In the spontaneous alopecia mice model, the hair growth effect from the cantharidin fraction (0.125%) was observed to be strong as compared with the states before the 13 days experiment. These experiments suggest that extracts and fractions of Mylabris phalerata Pall. may stimulate the topical hair growth activity in low doses.