Gene action for some economical traits in squash was examined by 6 x 6 diallel crossing excluding reciprocals using four foreign varieties, as well as, two local varieties. These varieties were belonging to the species of Cucurbita pepo, L. All 21 genotypes , included  six parents and their 15 F₁ hybrids were evaluated in the following two locations; Sakha Research Station in Kafr El-sheakh and private farm at Mansoura-  Dakahila governorate. Data of vegetative and flowering traits were recorded on plants within plots on the two types. The obtained results revealed that the mean squares of genotypes and its components, GCA and SCA were highly significant for all studied traits, indicating that additive and non-additive genetic variance contributed in the inheritance of the studied traits.                 Both GCA and SCA genetic variances were found to be highly significant for all studied traits indicating the importance of both additive and non-additive gene action.                 The parental, Zucchino Nova Verde di Milano were seemed to be the best combiner for number of leaves plant^-1 and No. of male flowers plant^-1. While, Arab Marrow was the best combiner for stem length, leaf area (cm²) and No. of female flowers plant^-1. The crosses involving the above parents were promising because they showed highly significant estimates of SCA effects.