In order to study the mechanism of the transgenic male sterility induced by the antisense fragment of gene CYP86MF, some physiological and biochemical indexes were compared between the transgenic plantlets of Chinese cabbage-pak-choi(Brassica campestris L. ssp. chinensis Makino)and their controls. Results showed that there was significant difference between content of the endogenous hormones in leaves and floral buds. GA3 contents in leaves of the transgenic plantlets of B. campestris L. ssp. chinensis Makino cv. Shanghai-qing and cv. Youqing were reduced by 31. 72 and 46. 88% respectively as compared with those of their controls, and GA3 contents in floral buds of them were reduced by 62. 92 and 80. 57 % respectively. In addition, ZT contents in leaves of cv. Shanghai-qing and cv. Youqing were reduced by 11. 81 and 181. 20% respectively as compared with those of their controls and those in floral buds were reduced by 105. 94 and 128.75 % respectively. But, ABA content in transgenic plantlets was signif In order to study the mechanism of the transgenic male sterility induced by the antisense fragment of gene CYP86MF, some physiological and biochemical indexes were more between the transgenic plantlets of Chinese cabbage-pak-choi (Brassica campestris L. ssp. Chinensis Makino) and their controls. Results showed that there was significant difference between content of the endogenous hormones in leaves and floral buds. GA3 contents in leaves of the transgenic plantlets of B. campestris L. ssp. chinensis Makino cv. Shanghai-qing and cv. Youqing were reduced by 31. 72 and 46. 88% respectively as compared with those of their controls, and GA3 contents in floral buds of them were reduced by 62. 92 and 80. 57% respectively. In addition, ZT contents in leaves of cv. -qing and cv. Youqing were reduced by 11. 81 and 181. 20% respectively as compared with those of their controls and those in floral buds were reduced by 105. 94 and 128.75% respectively. But, ABA content in transgenic pl antlets was signif