【Objective】 The effects of chitosan on growth and development of Dioscorea bulbifera L. stems was studied to facilitate its commercial production. 【Method】Single factor four-level group experiments were conducted， in which Dioscorea bulbifera L. stems having single bud were cultured in MS+KT （2mg/L）+NAA（0.5mg/L） culture medium. The concentration of chitosan was 0（CK）， 0.5， 1.0 and 2.0 g/L. Various morphological indexes of Dioscorea bulbifeia L. plantlets were observed regularly and data was analyzed statistically. 【Result】Low concentration of chitosan enhanced the root and bud elongation to some extent in D. bulbifeia and the effect was most significant at 0.5 g/L concentration of chitosan. High concentration of chitosan inhibited the growth of root and bud in D bulbifeia stems. At 1.0-2.0 g/L concentrations， the effects were more pronounced. Chitosan also reduced the leaf growth of D bulbifeia plants， and the effects were more pronounced at its 1.0 g/L concentration. 【Conclusion】Low concentration of chitosan promoted the growth and development of D. bulbifeia stems， while high concentration of chitosan showed contrary results.