Abstract：Objective：To observe the nursing effect of external application of Ruyi Jinhuang powder on the prevention of phlebitis caused by needle retention of superficial vein，and observe the local redness and swelling. Methods：A total of 86 patients with phlebitis caused by needle retention of superficial vein were divided into the control group and the study group according to the order of admission，43 cases in each group. The control group was given wet application of 50% magnesium sulfate gauze，and the study group was externally applied with Ruyi Jinhuang powder. The clinical therapeutic effect， cure time， pain degree， and the incidence of adverse reactions were respectively compared between the two groups. Results：The total effective rate was 95.35% in the study group and 79.07% in the control group，the difference being significant(P＜0.05). The cure time and pain degree in the study group were better than those in the control group，the difference being significant(P＜0.05). The total incidence of adverse reactions was 4.65% in the study group and 23.26% in the control group，and the study group had fewer adverse reactions than the control group，the difference being significant (P＜0.05). Conclusion：Compared with the wet application of 50% magnesium sulfate gauze，the external application of Ruyi Jinhuang powder has accurate therapeutic effect on phlebitis caused by needle retention，which can reduce local redness and swelling and other adverse reactions，shorten the recovery time and effectively improve the prognosis.