Objective: To research the clinical effect of danshen injection combined with cimetidine in the treatment of pediatric allergic purpura and evaluates the safety of it. Methods: Selected 86 cases of children with pediatric allergic purpura who came to our hospital for treatment, and they were randomly divided them into observation group and control group, 43 cases in each group. The patients in the control group were treated with cimetidine, while the patients in the observation group were treated with danshen injection on the basic of control group. Compared and analyzed the clinical effect and adverse reactions of the two groups. Results: The total clinical effect of the observation group was 93.0%, which is obviously higher than the 76.7% in the control group, the difference between two groups is statistically significant (P<0.05); after the treatment, the lost time of clinical symptoms (such as rash, joint pain, gastrointestinal symptoms, purpura, and abdominal pain) of the patients in the observation is significantly lower than that of control group, the difference between them have statistical significance (P<0.05); compared with the data before treatment, the observation group and control group in lymphocytes CD3+, CD4+, CD9+ were significantly improved, the differences were statistically significant, the observation group improved more significantly than the control group (P<0.05); after the treatment, the rate of adverse reactions of the patients in observation group is 7.0%, which is significantly lower than that of 18.6% of the control group (P<0.05); after 1 year of follow-up, the recurrence rate of the observation group is 14.0%, which is obviously lower than that of 39.5% of the control group (P<0.05). Conclusion: Applying the danshen injection combine with cimetidine in the treatment of child’s pediatric allergic purpura have great clinical effect, it can effectively improve the lymphocyte function disorder, which is y safety and worthy of application.