Rosmarinus officinalis is a common household plant with needle-like leaves and white flowers belongs to the family Lamiaceae and has various medicinal properties including cardiovascular, nervous disorders, gastrointestinal, genitourinary conditions, liver diseases and scalp treatment. The present research is envisaged on formulation and evaluation of 1% herbal hair lotion incorporated with methanolic extract of R. officinalis. The aerial parts of R. officinalis was extracted with methanol and subjected to preliminary chemical tests. It showed the presence of proteins, aminoacids, fats and oils, steroids, glycosides, phenolic compounds, flavonoids, volatile oil and vitamins. The extract was formulated to a suitable hair lotion and then evaluated for its various quality control parameters. Finally, the lotion was evaluated for hair growth promoting activity on C57BL/6 mice, using water as control and 2% minoxidil hair lotion as standard. It was observed that the formulated 1% herbal hair lotion passed all the evaluation parameters and showed a significant hair growth promoting activity than the standard drug treated animals. From this study it can be concluded that R. officinalis can be considered to be a better choice for the synthetic hair growth promoters which have unwanted side effects.