This work was conducted to study the effect of genotypes, sucrose concentrations and their interaction on induction of haploid plants of summer squash cultivars through anther culture. Therefore, four squash varieties and their six F₁ hybrids, which produced according to half diallel crosses, were used in this study. Anthers were placed on MS medium supplemented with three different concentrations of sucrose (30, 60 and 90 g/l). Data were recorded for the traits of responding anthers (R.A), callus weight / responding anthers (C.W/R.A) and shoot ratio (Sh.R). The results from the combined data revealed that the mean squares of genotypes indicated the presence of highly significant differences between these genotypes for callus weight / responding anthers and shoot ratio, while the responding anthers trait was insignificant. In addition, Eskandrani was the best combiner for callus weight / responding anthers and shoot ratio traits which had the highest significant positive GCA effect values. Furthermore, the results revealed that the cross Eskandrani x Baladi was the best combination for responding anthers. In addition, the cross Baladi x Zucchini was the best combination for callus weight / responding anthers. While, the combination between Eskandrani and Zucchini was the best regenerable, which had a positive and highly significant SCA value for shoot ratio. The results also showed that dominance genetic variance seemed to be more important than additive genetic variance with respect to the anther culture ability components at each concentration of sucrose, indicating the predominance of dominance gene effects in the inheritance of these in vitro traits. These results could be emphasized by dominance degree ratio, which was more than unity for all studied traits, revealing the importance of over-dominance in the expression of these traits. In general, the present results confirm the fact of the predominance of non-additive gene action in the genetic expression of the studied traits. It could be recommended the hybrid production as breeding programme for improving these traits. Keywords: