© 2018, Springer-Verlag GmbH Germany, part of Springer Nature. Purpose: The objective of this study was to investigate the effect of renin–angiotensin system inhibitors (RASIs) on bevacizumab (BV)-induced proteinuria in non-small cell lung cancer (NSCLC) patients. Materials and methods: We retrospectively reviewed the medical records of NSCLC patients receiving BV between 2008 and 2014 at 11 hospitals. The patients were categorized into three groups according to their antihypertensive drug use: RASI user, non-RASI user, and non-user groups. The primary outcome was a proteinuria event of any grade during the first 6 cycles of BV treatment. Results: A total of 211 patients were included, 89 of whom received antihypertensive drugs. Of these 89 patients, 49 were in the RASI user group, and 40 were in the non-RASI user group. The non-user group comprised 122 patients. The occurrence of proteinuria in the RASI user group was significantly lower than that in the non-RASI user group (P = 0.037) but was not significantly lower than that in the non-user group (P = 0.287). Patients using RASIs had a lower rate of proteinuria than those who did not use RASIs according to multivariate analysis (odds ratio 0.32; 95% confidence interval 0.12–0.86; P = 0.024). Conclusion: Our study suggests that RASI administration reduces the risk of proteinuria in patients receiving BV.