This study aims to explore the improvement and the mechanism of the Alisma plantago-aquatica Linn. (ApL) on chronic glomerulonephritis (CGN). All animal experiments were followed the regulation of the Experimental Animal Ethical Committee of Shanghai University of Traditional Chinese Medicine. CGN mouse model was established by a single tail-vein injection of doxorubicin (Dox) (20 mg·kg^-1). One week after Dox administration, the mice received water extract of ApL (85 and 255 mg·kg^-1) by gavage once a day for 14 days. At the end of experiment, the urine albumin-to-creatinine ratio (ACR), serum albumin (ALB), blood urea nitrogen (BUN) and serum creatinine (SCr) were detected, kidney histopathological H&E staining was analyzed. Active ingredients and action targets of ApL were collected from TCMSP database, and CGN-related targets were obtained from Genecards database. STRING platform was employed to perform protein-protein interaction (PPI), and Metascape platform was used for KEGG pathway and GO enrichment analysis. The results of experiments demonstrated that ApL (85 and 255 mg·kg^-1) could reduce the ACR and the content of SCr and BUN, and increase the content of ALB in mice. Network pharmacology results predicted that nuclear factor kappa-B (NF-κB)-related pathway and biological process of oxidoreductase activity regulation may be involved in the ApL-provided amelioration on CGN. The verification results showed that ApL could inhibit the activation of NF-κB and the expression of inflammatory factors in mice, and reduce the activity of renal myeloperoxidase (MPO). Meanwhile, ApL promoted the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) and increased the expression of its downstream gene mRNA, and reduced the level of renal malondialdehyde (MDA) and reactive oxygen species (ROS), and further elevated renal glutathione (GSH) level. Based on network pharmacology combined experiments, this study found that ApL may improve CGN in mice through multiple targets and multiple pathways, in which the inhibition of NF-κB signaling and the activation of Nrf2 signaling may be important mechanisms involved.