Objective To investigate the effect of irbesartan and Shenyan Kangfu Tablet on renal function in chronic nephritis. Methods A total of 80 patients of chronic nephritis admitted in our hospital from March 2018 to August 2020 were randomly selected and divided into two groups by drawing lots. The control group (40 cases) received irberartan, while the research group added Shenyan Kangfu Tablet on the basis of irberartan. The renal function indexes, clinical efficacy and adverse reactions of the two groups were compared. Results After treatment, renal function indexes in both groups were improved, and serum creatinine, urea nitrogen and 24 h urinary protein levels in the research group were lower than those in the control group, and glomerular filtration rate was higher than that in the control group (P<0.05). The total effective rate was significantly different between the two groups (P<0.05), but there was no difference in adverse reaction rate. Conclusions In the treatment of chronic nephritis, irbesartan combined with Shenyan Kangfu Tablets could effectively improve renal function, and the effect is significant.