A simple protocol for in vitro mass propagation of Gentiana davidii var. formosana (Gentianaceae) has been developed. Multiple shoot development was achieved by culturing the stem node explants on Murashige and Skoog (MS) medium supplemented with 4.44 microM N6-benzyladenine (BA). The shoots were multiplied by subculturing on MS medium supplemented with 1.07-10.74 microM alpha-naphthaleneacetic acid (NAA) and 8.88 microM BA. Shoots were rooted on MS basal medium supplemented with various auxins. Shoots rooted on growth regulator-free medium were transferred to peat moss:vermiculite mixture and acclimatized in the growth chamber. The contents of gentiopicroside and swertiamarin, the two important secoiridoid glucosides, in different plant material were determined by high performance liquid chromatography (HPLC). The analysis revealed that the content of gentiopicroside and swertiamarin in the aerial and underground parts of G. davidii var. formosana was higher than the marketed crude drug (underground parts of G. scabra) and varied with the age of the plant.