For a long time, no attempts were made to improve gurma melon characteristics or to develop new hybrids. So, this investigation was conducted to identify desirable parents and cross combinations as well as to gather information on genetic behavior of gurma melon yield and yield component traits. In this respect, a diallel cross without reciprocals, was made among five parental inbred lines of gurma melon in S₆ generation, that were selected in an earlier study through self-pollination and selection program for the commercial cultivar. All 10 F₁ hybrids with their parents were evaluated. The results showed high value of coefficient of heritability for all the studied traits (fruit weight, number of fruits/plant, seeds weight/fruit, 100-seed weight and seed yield/plant). This finding indicates a scope for improvement these characters through selection and hybridization. The results also indicated that line 3 and line 4 were the best combiner parents when crossed with the other parents with regard to seed yield traits. Moreover, the hybrids 2×3, 2×4 and 3×4 were the best cross for seed yield per plant. In addition, heterosis that was strongly expressed in case of number of fruits/plant, seeds weight/fruit and seed yield/plant would justify the commercial utilization of hybrid vigor in gurma melon. On the other hand, seed yield per plant showed positive significant genotypic and phonotypic correlations with seeds weight/fruit and 100-seed weight, thus, selection for increasing any one of these   traits would certainly increase seed yield. Generally, the results showed that the possibility of using these new lines to generate desirable new hybrids for gurma melon.