Shengyang Yiwei Decoction showed efficacy in idiopathic membranous nephropathy treatment, and this study aimed to assess the underlying molecular mechanisms.Rats with passive Heymann nephritis were divided into the model group, the Shengyang Yiwei Decoction group, the JAK2 inhibitor group, and the STAT3 inhibitor group. Healthy rats served as the normal control. 24-hour urinary protein excretion, IgG deposition, renal histopathology, the expression levels of synaptopodin, nephrin, podocalyxin, interferon-γ, interleukin- 4, T-box expressed in T cells, GATA binding protein-3, and relevant pathway proteins were measured.Within the model group, a notable elevation in the 24-h urinary protein level was observed, accompanied by evident IgG deposition, increased glomerular volume, eosinophilic deposits, diminished expression of podocyte marker proteins, and a discernible imbalance in Th1/Th2 cellular immunity. Conversely, in Shengyang Yiwei Decoction and both inhibitor groups, enhancements were observed across the aforementioned indexes.Shengyang Yiwei Decoction may reduce glomerular podocyte injury through the suppression of the JAK2/STAT3 signaling pathway and modulation of the Th1/Th2 immune balance.Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.