Abstract： Objective To investigate the changes of serum vitamin D levels in primary hypertension patients.Methods According to risk factors,56 patients were selected as low risk group; 53 patients were selected as intermediate risk group; 31 patients were selected as high risk group and 33 healthy subjects were selected as normal control group.The 25-hydroxyvitamin D3 was measured with enzyme-linked immunoassay(ELISA).The statistical data was analyzed by SPSS 18.0 software.Results The sex and age of four groups objects were not significantly different.The 25 (OH) D3 of low risk group was (27 ± 6)μg/L; the 25 (OH) D3 of intermediate risk group was (27 ± 5) μg/L.The 25 (OH) D3 of high risk group was (21± 5)μg/L.The 25 (OH) D3 of the healthy subjects was (32 ± 8) μg/L.The 25 (OH) D3 of low risk and high risk and the healthy groups objects were significantly different (P＜0.05).With simple regression analysis,the 25 (OH) D3 was positively associated with systolic pressure and diastolic pressure (r =-0.412,-0.377,all P ＜ 0.01),but not significantly associated with the parathyroid hormone,calcium,phosphorous and age.Conclusion There is a high level of hypovitaminosis D in primary hypertension patients.