Abstract: Seeds of 5 varieties of Chamaecrista spp. were irradiated with⁶⁰Co γ-ray at a radiation dosage of 300Gy and a radiation rate of 4 .6875 Gy/min.Observations and selection were made at M₁ and M₂.Then nutrient measurement at M₃ was started with plants selected from mutants of the 5 varieties.Results show that K content of “ATF2219” decreases significantly,while no significant differences in N,P and K contents of other varieties are found.Total amino acid content of “ATF2219” decreases significantly with 17 kinds of the amino acids showing some degree decrease.Total amino acid content of “CPI86134” increases significantly with 17 kinds of the amino acid showing some degree increase.There are no significant differences in the other varieties. RAPD analysis shows that offsprings of the 5 irradiated varieties are significantly genetically different from CK.