Objective To investigate the effect of controlling blood pressure in treating patients with hypertension by taking quantitative vitamin D to provide support for the clinical treatment of patients with hypertension.Methods 100 cases with hypertension were randomly divided into the two groups voluntarily,50 cases in each group and one group with a simple standard treatment was considered as the control group,and the other one was the study group,25μg/d vitamin D was taken besides standard treatment.Each group content of 25-hydroxyvitamin D [25 (OH)D] level were measured by Enzyme-linked immunosorbent assay (ELISA) and lasted for one year to detect the situation of controlling blood.Mean and variable coefficient of systolic and diastolic blood pressure were calculated and compared each other.Results After treatment,the content level of 25 (OH)D was (110.3 ± 24.5)nmol/L,systolic pressure was (144 ± 16) mmHg,variable coefficient was 11.1％,diastolic pressure was (87 ± 9) mmHg,variable coefficient was 10.3％ in experiment group;while the content of level of 25 (OH)D was (30.1 ± 14.9)mol/L,systolic pressure was (145 ± 26)mmHg,variable coefficient was 17.9％,diastolic pressure was (87 ± 10)mmHg,variable coefficient was 12.4％ ;the content of level of 25 (OH)D,variable coefficient of systolic pressure had statistical difference (t =12.47,x2 =6.72,P ＜ 0.01),variable coefficient of diastolic pressure had no statistical difference (P ＞ 0.05).Conclusion Taking quantitative vitamin D besides standard treatment is benefit for controlling the level of systolic pressure in patients with hypertension but is meaningless to the level of diastolic pressure.