This paper measured the ethylene release rates in different cucumber genotypes including ffMMaa，ffMMAA，FFMMaa，FFMMAA，and FFmmAA by gas chromatography，to study the relationship between ethylene and cucumber sex genotypes. The results showed that there were significant differences between the ethylene release rates in the near-isogenic lines. The ethylene release rate of ffMMaa in androecious 78 ♀ was the lower. That of ffMMAA in monoecious 406 at the 4-leave stage was higher than at the 2-leave stage. The ethylene release rate of gynoecious 10098♀ with FFMMaa genotype，which had 6.33 F gene copies was lower than that of the gynoecious WI1983G with FFMMAA genotype，which had 2.15 F gene copies. The ethylene release rate of gynoecious WI1983G（FFMMAA） was extremely significantly higher than nearly isogenic line hermaphrodite WI1983H（ FFmmAA），while that of WI1983H was extremely significantly higher than that of monoecious WI1983GM（ ffMMAA）. These facts indicated that cucumber sex genotype was closely associated with endogenous ethylene. The low ethylene release rate in androecious（ ffMMaa） might be associated with A gene inactivation. The ethylene release rate of gynoecious（ FFMMaa）could be regulated by A/a gene. Although M gene in hermaphrodite （FFmmAA） was inactive，endogenous ethylene release rate did not reduce much，the endogenous ethylene synthesized by F gene might have not directly affected the stamens inhibition in bisexual flower.