The effects of light on photosynthetic characteristics, growth and accumulation of effective components of Dendrobium huoshanense test-tube seedlings were studied in this paper. The results of single factor experiments showed that the optimal light intensity was 30 μmol·m-2·s-1, the best illumination time was 12 h·d-1, and the most suitable light quality was red light. The results of multi-factor experiments were as follows: the light conditions which were benefi cial to growth of test-tube seedlings were r...