Abstract: The contents of endogenous hormones and polyamines in leaves were measured by HPLC in female and male plants of Trichosanthes kirilowii Maxim during their developmental stages. The results showed that great difference in endogenous hormones existed between female and male plants. The contents of IAA in female plants were always higher than those of male plants. However，the contents of ABA in female plants were always lower than those of male plants. During the vegetative growth stage，the contents of GA1/3 and ZR in male plants were higher than those of female plants，then the contents of GA1/3 and ZR both decreased rapidly during the reproductive growth stage of male plants. However，the contents of GA1/3 and ZR in female plants were continuously increased until the end of female’s vegetative growth and then also decreased rapidly. The Spd contents in female plants were significantly higher than those of male plants. The Spm contents in male plants were higher than those of female plants during the vegetative growth stage. However, no significant difference of Spm contents existed between male and female plants during the reproductive growth stage of female plants. The Put contents in male plants were significantly higher than those of female plants during the vegetative growth stage. However，the Put contents in female plants were significantly higher than those of male plants during the early reproductive growth stage of female plants，thereafter，the Put contents were decreased and had no difference between male and female plants during the late reproductive growth stage of female plants. The results suggested that high contents of IAA and high Spd were beneficial to the development of female flowers，while high levels of Put and Spm were beneficial to the development of male flowers. Polyamines decreased after flowering of female and male plants except Spd. While the difference of Put and Spm content was lesser at the late reproductive stage. These results demonstrated that polyamines were concerned with sex determination and differentiation of Trichosanthes kirilowii.

Key words: Trichosanthes kirilowii Maxim, endogenous hormones, endogenous polyamine, growth and development stage, dioecy