Abstract: Twenty-eight C. moschata F1 hybrids involving 8 genotypes as parents (Pusa Vishwas, S-107-B, S-124-10, NDPK-24, S-15, S-12, S-20, and S-17) in half diallel fashion were evaluated to study the gene action of yield and its contributing characters. Dominant gene action was observed for all the characters, viz. vine length, fruit maturity, fruits per plant, fruit weight, and yield per plant. In all these characters, dominance component of variance was greater than the additive component of variance. The heritability in narrow sense was found to be less than 0.50 for the majority of characters. Low narrow sense of heritability coupled with higher degree of non-additive gene action (dominance variance) in yield and its components suggested that heterosis breeding might be advantageous for obtaining higher gains in pumpkin.