Objective: To observe the relationship of tumor necrosis factor-α (TNF-α) and nitrogen oxide (NO) with the treatment of frequent relapse nephrotic syndrome (FRNS) and to explore the pathogenesis of FRNS and the therapeutic mechanism of Shenkangling(肾康灵，SKL) Granule in children.Methods: Sixty children suffering from FRNS were randomly divided into the treated group and control group, 30 in each, and the other 30 healthy children were taken as healthy group. The patients were treated with prednisone for a long-term course, and those with no effect or partial effect shown were treated with additional Tripterygium or Cytoxan in the control group, while in the treated group patients were treated with prednisone and additional SKL. The two groups were compared as to their changes of TNF-α,NO before and after treatment, and the relapses after treatment. Results: The levels of TNF-α and NO in the sick children before treatment were markedly higher than those after treatment and normal group (P＜0. 01). The positive correlation between TNF-α of FRNS cases and relapse risk displayed more significance than that between the relapse of FRNS and NO. The difference between treated group and control group was significant (P＜0. 01). Conclusion: TNF-α can be regarded as the monitoring parameter of the active phase in FRNS, and the higher the level, the more possible the relapse would occur. SKL could markedly reduce the relapse rate of FRNS in children.