ObjectiveTo investigate the protective effects of Zuogui Wan （ZGW） decoction on nephrotic syndrome （NS） through the regulation of gut microbiota. MethodsThirty male Sprague-Dawley （SD） rats were randomly divided into five groups， with 6 rats in each group： The control group， model group， low-dose group， medium-dose group， and high-dose group. The NS rat model was induced by tail vein injection of 6.5 mg·kg^-1 doxorubicin. After successful modeling， the control and model groups were gavaged with normal saline （10 mL·kg^-1） twice daily， while the low- （50 mg·kg^-1）， medium- （100 mg·kg^-1）， and high-dose （200 mg·kg^-1） groups were gavaged with ZGW （10 mL·kg^-1） twice daily. All rats were administered at fixed intervals daily for 8 consecutive weeks. The therapeutic effects of ZGW on NS in rats were observed， and the optimal dose was screened. Renal and intestinal pathological changes in rats were examined. Fecal samples were collected， and 16S rDNA sequencing technology was used to detect the diversity and abundance of gut microbiota in each group. ResultsCompared with the control group， 24-hour urinary protein， serum creatinine， urea nitrogen， and cholesterol levels significantly increased in the model group （P<0.01）， while serum albumin levels decreased （P<0.01）. These changes were ameliorated in the treatment groups （P<0.05， P<0.01）. Renal pathology revealed intact and orderly arranged glomeruli and renal tubules in the control group. In the model group， glomerular atrophy， widened mesangial areas， podocyte swelling， disordered renal tubular arrangement， and numerous casts were observed. Varying degrees of glomerular atrophy and disordered renal tubular arrangement were seen in the treatment groups. Specific protein assays revealed increased serum levels of kidney injury molecule-1（KIM-1） and α1-microglobulin （P<0.01）， and significantly decreased levels of E-cadherin， Podocin， and Nephrin in renal tissues （P<0.01）， along with a significant increase in transforming growth factor-β（TGF-β） （P<0.01） in the model group. In the treatment groups， serum KIM-1 and α1-microglobulin levels decreased， E-cadherin levels significantly increased （P<0.01）， and TGF-β levels significantly decreased （P<0.01）. Podocin and Nephrin levels increased in the high-dose group （P<0.05）. Additionally， intestinal mucosal atrophy， epithelial cell edema， decreased goblet cells， and multiple inflammatory infiltrations were observed in the model group. The sequencing results of gut microbiota demonstrate that ZGW can significantly ameliorate intestinal dysbiosis in rats， restore the abundance of beneficial bacteria， and exert a profound influence on the compositional profile of gut microbiota. ConclusionZGW can alleviate renal injury in rats with nephrotic syndrome by improving gut microbiota and protecting the intestinal barrier.