To observe the therapeutic effect of Xueniaoan Tablets on immunoglobulin A(IgA) nephropathy(IgAN) rats and its impact on glomerular mesangial cell proliferation.Methods:Thirty Sprague-Dawley(SD) rats were randomly divided into control group,model group,and Chinese medicine group using a random number table.An IgAN model was established,and from the 10th week,the Chinese medicine group was orally administered with Xueniaoan Tablets,while the control and model groups were administered an equal volume of physiological saline.The 24-hour urinary protein quantification was measured at the 10th,11th,and 12th weeks.At the end of the 12th week,urinary creatinine,blood creatinine,and creatinine clearance rate were measured in each group.Kidney tissue was collected to observe pathological changes,and immunofluorescence was used to detect IgA.Immunohistochemistry was used to detect the expression of proliferating cell nuclear antigen(PCNA) in glomerular mesangial cells.Results:Compared to the model group,the Xueniaoan Tablets group showed a significant decrease in 24-hour urinary protein levels,an increase in glomerular creatinine clearance rate,a reduction in kidney tissue damage,lower IgA quantity and fluorescence intensity,and a reduction in PCNA expression in the glomerulus.Conclusion:Xueniaoan Tablets can reduce 24-hour urinary protein levels,delay the decline in kidney function,and alleviate kidney pathological damage in IgAN rats.The mechanism may be related to the inhibition of mesangial cell proliferation.