Abstract: In order to understand the genetic model of soluble solid content in Cucurbita moschata, the mixed major gene plus polygene inheritance model was used to investigate the inheritance of soluble solid content in the material of the six generations (P₁, P₂, F₁, F₂, BCP₁, BCP₂) derived from hybrid Cucurbita moschata. The results showed that the traits of soluble solid content were controlled by two major genes with additive-dominance-epistemic effects and polygenes with additive-dominance effects model in the joint analysis of six generations. The additive effects of the two major genes were -0.7077, indicated the reducing of the soluble solid content; the dominance effects of the two major genes were 3.5034 and 1.3586, respectively, indicated the increasing of the soluble solid content. The polygenes additive and dominance effect were 2.3066 and -0.6679, respectively. The major gene heritabilities of BCP₁, BCP₂ and F₂ populations were 17.06%, 56.01% and 95%, respectively, and the polygenes heritabilities of BCP₁, BCP₂ and F₂ populations were 47.16%, 18.78% and 0 respectively, it indicated that the higher hereditability of major genes could be favorable to an efficient selection in early generation of breeding. This research provided the theoretical basis for the selection of breeding quality traits and marker-assisted selection in Cucurbita moschata.