Abstract: Through the analysis of the sexual character ofmonoecious plants based on the ability of producing exclusively female flowers at later stages, monoecious cucumber could be divided into two groups of monoecious: common monoecious and monoecious-subgynoecious (MOA-subgynoecious). In the experiment, which 5 parental combinations from inbred two MOA-subgynoeciouses (98217, S22298) , monoecious (95) ,gynoecious (W I1983G) and hermaphrodite (W I1983H) and their F₂ , BC1 -1 , BC1-2 were as research materials. Genetic analysis showed the MOA-subgynoeciouswith the ability of producing exclusively female flowers at later stagerswere controlled respectively by one pair of incompletely dominant gene and one pair of recessive gene, which were respectively designated presently as Mod-F₁ and mod-F₂. Genes Mod-F₁ and mod₂F₂, which enhanced the intensity of femaleness, inherited independently with F and M genes.

Key words: Cucumber, Sex phenotype, Sex expression, Inheritance