This study was initiated to generate information about genetic variability, heritability and genetic advance of yield components in Citrullus mucosospermus. In this way, four inbred lines of C. mucosospermus were evaluated at Kononfla city in Western Côte d’Ivoire, using a randomized complete block design with three repetitions. The results of discriminant analysis indicated significant differences between four C. mucosospermus inbred lines what are Bebu, Wlêwlê small seeds 1, Wlêwlê small seeds 2 and Wlêwlê small seeds 3. Mahalanobis distances varied significantly from 8.44 to 629.50 between theses inbred lines. All investigated traits recorded high genotypic and phenotypic coefficients of variation values except fruit maturity period and fruit diameter where, low values were recorded. Studied morphological traits exhibited high heritability (H²> 80%) coupled with moderate to high genetic advance as percentage of mean. Stepwise regression analysis revealed mass of fresh seeds per fruit followed by mass of fruit, seed width, seed length and fruit maturity as traits contributing for linear increase in mass of dry seeds. These traits could be considered as key criteria for selecting high yielding line in C. mucosospermus breeding program at Côte d’Ivoire.