This study aimed to investigate the genetic parameters of ten Cucurbita pepo L. hybrid cultivars, including seven foreign hybrid cultivars (F1 Shiraz, F1 Khaleej, F1 Samar, F1 Roham, F1 Daphne, F1 Asma and F1 Oto) and three domestic hybrid cultivars (F1 Peronesh, F1 BL and F1 CL) in the form of a randomized complete block design with 3 replications at the Pest Investigation Research Station and the Shahid Fozveh Research Station of Isfahan, central Iran, in 2019. The bed preparation operation was done and the seeds were sown in the mid-June. The results showed that the highest fruits/plant was observed in CL and Shiraz genotypes and the highest yield/plant in four harvests was observed in Peronesh genotype. Roham and Otto genotypes showed the lowest total yield/plant. BL genotype showed the highest mean fruit diameter in four harvests and the highest fruit weight of the seed sample. The highest seed weight was obtained in Shiraz and Asma genotypes and the highest seed-to-fruit weight ratio was obtained in Samar genotype. BL, Asma and Shiraz genotypes showed the highest seed dry weight. The highest seed length and the highest dry weight of 100 seeds were observed in Peronesh and BL genotypes. A positive and significant correlation was also observed between some traits. Among the investigated genotypes, Peronesh and BL genotypes outranked the other genotypes in most of the traits. Also, Shiraz genotype had a significant advantage in some seed traits compared to other genotypes. According to the presented results, different genotypes of the pumpkin plant were significantly different from each other in terms of various traits, indicating that the ground is prepared to employ these resources for improving the yield of this plant species.