Petroleum ether extract of leaves and flowers of Hibiscus rosa-sinensis was evaluated for its potential on hair growth by in vivo and in vitro methods. In vivo, 1% extract of leaves and flowers in liquid paraffin was applied topically over the shaved skin of albino rats and monitored and assessed for 30 days. The length of hair and the different cyclic phases of hair follicles, like anagen and telogen phases, were determined at different time periods. In vitro, the hair follicles from albino rat neonates were isolated and cultured in DMEM supplemented with 0.01 mg/ml petroleum ether extract of leaves and flowers. From the study it is concluded that the leaf extract, when compared to flower extract, exhibits more potency on hair growth.