Trifolium tomentosum L. is an annual plant in the Mediterranean and western part of the Iran-Turanian region, which is also found in the west and southwest of Iran. Due to its high tolerance to saline and flood soils and the suitability of feeding livestock, this can be a good alternative to rangeland rejuvenation. This species has three varieties of tomentosum, curvisepalum and chthonocephalum in Iran. This study investigates genetic variation and relationships in 40 individuals from 10 populations of this species using CDDP method. Out of 12 primers, 117 bands were obtained, of which 115 (98.29%) were polymorphic. Based on the results of cluster analysis, the samples were classified into two distinct groups, the first cluster including var. tomentosum and the second cluster including curvisepalum and chthonocephalum varieties. The mean genetic variation of Nie (H) and Shannon's information index (I) were highest in var. chthonocephalum. The analysis of molecular variance also showed that the intra-population genetic diversity (62%) was higher than inter-population genetic variation (38%), which confirms the outbreeding of this species. In general, according to the results of this study, curvisepalum and chthonocephalum varieties of T. tomentosum are more similar, which are not consistent with the results of older studies based on SSR and IRAP markers, and it can be said that the varieties of T. tomentosum are very similar and the molecular markers cannot separate the varieties of this species well
