Abstract: To assess the adaptation of Lycopus lucidus Turcz.var. hirtus Regel. under drought stress，seedlings of Lycopus lucidus Turcz.var. hirtus Regel were used as materials to study the growth， physiological and biochemica characters under conditions of four artificial controlled drought treatments （20%， 40%， 60% and 80%）. The results showed that the growth of height and leaf area declined with the increase of drought stress; the MDA contents increased under drought stress; Chl a， Chl b and carotenoid contents were increased under the moderate drought while decreased under the severe stress. For the Lycopus lucidus Turcz.var. hirtus Regel. seedlings， the 40% soil water condition was the threshold at which the negative effect of drought on the physiological and biochemical activities of the leaves was observed.

Key words: Lycopus lucidus Turcz.var. hirtus Regel., water stress, growth, MDA, photosynthetic pigment