The study was conducted to determine genetic variability and correlation involving 21 watermelon genotypes in a randomized block design with three replications. A considerable amount of variability was observed for qualitative and quantitative traits. Maximum phenotypic and genotypic variability was recorded for the seediness, followed by pericarp thickness and fruit weight. Most of the characters except cotyledon size, leaf blade ratio, emergence of first male flower, emergence of first female flower, days taken to fruit maturity, blooming period and seed length exhibited high estimates of heritability coupled with the high estimates of genetic advance. Number of fruits per vine had significant genotypic and phenotypic positive correlation with the traits leaf blade length, internodal length, number of primary branches and number of secondary branches. Based on yield and yield contributing characters, the genotypes viz., VRW-14, VRW-12, VRW- 20 and VRW-17 were found promising for future improvement programme.

The results of the analysis of variance indicated that substantial genetic variability was present for yielding contributing characters. The intra-cluster distance was recorded as the highest for cluster 3 (49.75) which indicates the existence of maximum variability within this cluster. The inter-cluster distance was maximum between clusters 5 and 6 (94.81) which indicates that the genotypes included in these clusters are genetically diverse. So, it is desirable to select accessions from the clusters having high inter-cluster distance in the recombination breeding programs. The minimum inter-cluster distance was observed between cluster 1 and cluster 5 (50.92), indicating the close relationship among the genotypes included in these clusters. Based on yield and yield contributing characters, the genotypes viz., VRW-14, VRW-12, VRW- 20 and VRW-17 were found promising for the future improvement programme.