The objective of this study was to evaluate seed characteristics of sponge gourd, to establish a core collection of sponge gourd with the germplasm collected throughout the Hatay region. A mini-core collection was assessed for morphological performance and some seed traits. Substantial variations of seed characteristics: seed length, seed width, seed thickness (mm), seed index (length/width), seed size (length × width, mm2), seed colour, seed-coat surface, seed shape, seed wing, and 100-seed weight were investigated. Seed length, width and thickness were varied as 15.12-8.97 mm, 9.71-6.25 mm and 2.86-2.16 mm respectively. The seed sizes were determined from small (31 DÖ 06) to big (31 DE 04). Seed colours were ranged from black to white, even a brown colour like 07 MA 01. A hundred seed weights were observed as 16.43 g (31 AL 02) and 7.41 (31 DÖ 06). The results of dendrogram indicated that seed traits of the sponge gourd genotypes were separating in five groups. This collection of sponge gourds will be useful for the gene pools and a wide range of phenotypic variations to provide a good source of diversity for developing of sponge gourd cultivars in breeding programs.