The effects of light on the growth and ginsenosides production were examined in the hairy roots of Panax ginsen C.A. Meyer induced by Agrobacterium rhizogines A4. The 9rowth of ginseng hairy roots in 1/2MS liquid medium was significantly decreased with an increment of light intensity (1,000~7,000 lux). The growth of hairy roots under 7,000 lux condition was decreased at 17% compared to the dark condition. The production of 7 ginsenosides in hairy root was very high in 3,500 lux condition. The production of ginsenoside-Rg, and Rf increased 3.3 and, 2.4 times respectively as compared to dark condition. The growth of hairy roots was inhibited by blue light, while ginsenosides production was increased. The sucrose demands of hairy roots was examined in light condition(3,500 lux). The growth of hairy roots in 1/2MS liquid medium with various sucrose concentrations(1~4%) was high in IVp sucrose, while ginsenosides production was high in 3% sucrose condition. The growth and ginsenosides production were high when hairy roots were cultured in dark condition for 1 week and then transferred to light condition(3,500 lux) for 4 weeks. It is suggested that ginsenosides production could be accelerated by light intensity of specific wavelength in cultures of ginseng hairy roots.