OBJECTIVE:To observe clinical efficacy and safety of milrinone in the treatment of persistent pulmonary hyperten-sion of newborn. METHODS:52 newborns with persistent pulmonary hypertension were divided into control group and observa-tion group according to random number table,with 26 cases in each group. The control group were given mechanical ventilation and intravenous prostaglandin therapy. Observation group was treated with Milrinone injection at loading dose of 50 μg/kg,10 min intravenous injection,maintenance dose of 0.75 μg/(kg·min). Both groups received treatment for 48 h. Clinical efficacies of 2 groups were compared as well as SpO2,PaO2,OI,PAP,PAMP and SV before and after treatment. The occurrence of ADR was compared between 2 groups. RESULTS:Total effective rate of observation group was 92.31%,which was significantly higher than 80.77% of control group,with statistical significance (P<0.05). Before treatment,there was no statistical significance in SpO2,PaO2,OI,PAP,PAMP and SV levels between 2 groups(P>0.05). After treatment,above indexes of 2 groups were im-proved significantly;SpO2,PaO2,OI and SV levels of observation group were significantly higher than those of control group, while PAP and PAMP levels were significantly lower than those of control group,with statistical significance(P<0.05). No obvi-ous ADR was found in 2 groups. CONCLUSIONS:Milrinone shows significant therapeutic efficacy in the treatment of persistent pulmonary hypertension of newborn,and can significantly improve persistent pulmonary hypertension and increased oxygen con-tent of blood with good safety.