Callus was derived from the leaves of Scutellaria baicalensis Georgi. The productions of baicalin in the cultivated callus under various conditions, especially, the effects of the light sources and temperature were studied. In this experiment, the callus cultivated at $25^{circ}C$ showed higer production of baicalin than the callus cultivated at $21^{circ}C$ and $23^{circ}C$. The illumination of light(fluorescence and UV) accelerated generally the growth of callus and the production of baicalin during the cultivation for three weeks. But, the illumination of light more than three weeks reduced the rate of production of baicalin in the callus.