In this study, two cultivated species and their four wild species and three wild relatives of Corchorus were used to study chromosome number and karyotype of Corchorus by applying root tip squash method. The results showed that chromosome number in all of the materials was 2n=14 and the karyotype formulas were as follows: kuanye long-capsule cultivars of jute(C.olitorius) 2n=2x=14=14m(4SAT); Nanyang long-capsule wild species of jute (C.olitorius) 2n=2x=14=14m(2SAT); Tanzania long-capsule wild species of jute (C.olitorius) 2n=2x=14=2M+12m; Min ma No. 5 (C.capsularis) 2n=2x=14=12m+2sm；Aidian boll wild species of jute(C.capsularis) 2n=2x=14=14m ；Lianjiang boll wild species of jute (C.capsularis) 2n=2x=14=4M+10m；C.aestuans 2n=2x=14=2M+12m; C.pseudo-olitorius 2n=2x=14=2M+12m; Tianma (wild relatives of jute) 2n=2x=14=14m. Except kuanye long-capsule cultivars were 1B type, all of the karyotypes belonged to 1A type. The taxonamic status of Tianma has also been discussed in this paper.