To study immune function of children viral myocarditis and to evaluate the clinical effect of Shuanghuanglian Powder (SHLP) by injection. Methods: The 62 patients of viral myocarditis were divided into two groups randomly, the SHLP group (n=32) treated with conventional therapy plus SHLP and the conventional treatment group (n=30) with conventional therapy alone. Their serum antibody of Coxsackie virus group B (COXB IgM), T lymphocyte subsets including CD + 3, CD + 4, CD + 8 and CD + 4/CD + 8 were determined with ELISA and indirect immunofluorescent assay. Results: COXB IgM was positive in 39 of the 62 patients, which was significantly different with those of normal controls ( P <0.001). Patients’ serum level of CD + 4 cells and CD + 4/CD + 8 ratio decreased while CD + 8 increased. After treatment, the recovery of symptoms, signs and immune function in patients of the SHLP group were significantly better than those in patients treated with conventional treatment alone (P<0.01). Conclusion: Immunoregulatory disturbance is involved in children with viral myocarditis and SHLP is an effective drug in the treatment of children viral myocarditis. Method: The 62 patients of viral myocarditis were divided into two groups randomly, the SHLP group (n=32) treated with conventional therapy. Plus SHLP and the conventional treatment group (n=30) with conventional therapy alone. Their serum antibody of Coxsackie virus group B (COXB IgM), T lymphocyte subsets including CD + 3, CD + 4, CD + 8 and CD + 4/ CD + 8 were determined with ELISA and indirect immunofluorescent assay. Results: COXB IgM was positive in 39 of the 62 patients, which was significantly different with those of normal controls (P <0.001). Patients’ serum level of CD + 4 cells and CD + 4/CD + 8 ratio decreased while CD + 8 increased. After treatment, the recovery of symptoms, signs and immune function in patients of the SHLP group were significantly better than those in patients treated with conventional treatment Alone (P<0.01). Conclusion: Immunoregulatory disturbance is involved in children with viral myocarditis and SHLP is an effective drug in the treatment of children viral myocarditis.