The factors of effect on rooting of Mentha piperita L.plantlets are investigated.The results show that basic medium types and phytohormone concentrations are effective factors on rooting.The optimizing medium for rooting of tube plantlets of M.piperita is 1/2 MS containing 0.5 mg·L-1 6-BA and 0.3 mg·L-1 NAA.The better conditions for rooting of transferring plantlets are soaking shoots in solution containing 100 mg·L-1 6-BA and 50 mg·L-1 NAA for 30 min or in solution containing 50 mg·L-1 6-BA and 25 mg·L-1 NAA for 60 min.