Variability in seed traits and oil content of 24 accessions of Jatropha curcas collected from different agroclimatic zones of Haryana state, India were assessed. There were significant differences (P<0.05) in seed size, 100-seed weight and oil content between accessions. Maximum seed weight was recorded in seeds collected from IC-520602 and the least weight was recorded in IC-520587. Oil variability ranged from 28.00% in IC-520589 to 38.80% in IC-520601. In general phenotypic coefficient of variation was higher than the genotypic coefficient of variation indicating the predominant role of environment. High heritability and genetic gain were recorded for oil content (99.00% and 18.90%) and seed weight (96.00% and 18.00%), respectively, indicating the additive gene action. Seed weight had positive correlation with seed length, breadth, thickness and oil content. On the basis of non-hierarchical Euclidian cluster analysis, six clusters were obtained with highest number of accession falling under cluster III. Maximum and minimum intra cluster distance was observed for cluster VI (2.499) and for cluster III (2.252), respectively. Whereas maximum inter-cluster distance was observed between cluster VI and IV (5.129) and minimum between cluster III and II (2.472). Among the six clusters formed cluster IV showed maximum cluster value for seed size whereas, cluster VI showed maximum value for oil content and seed weight. Thus on the basis of present finding it is suggested that the crossing between accessions of cluster IV and VI will result in wide spectrum of variability in subsequent generations. (C) 2007 Published by Elsevier Ltd.