Objective: We aimed to study whether long-term kidney function would be affected by different chemotherapy regimens in patients with malignancy.Methods: In this study, 500 cancer patients between the ages of 18 and 85 years were included. Estimated glomerular filtration rate (eGFR) calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula was used to evaluate renal function. Patients with eGFR less than 60 mL/min/1.73 m2 before chemotherapy were excluded. Demographic and clinical data were recorded. Patients were divided into 4 groups according to the chemotherapy protocols: cisplatin-containing regimens, carboplatin-containing regimens, oxaliplatin-containing regimens, and platinum-free regimens. eGFR, urea, and creatinine values of 0th, 7th, 30th,and 180th days were recorded.Results: In 180 days of treatment, eGFR decreased in 69 (13.8%) patients, whereas it increased in 46 (9.2%) patients (P = .001) and remained unchanged in 385 patients (77%). The cisplatin group had lower eGFR at the 180th day compared to the carboplatin (P = .033), oxaliplatin (P = .007), and platinum-free groups (P < .001). The median eGFR at the 180th day was lower in the cisplatin group compared to baseline (P < .001), while eGFR levels were not changed in the carboplatin and oxaliplatin groups and were significantly increased in the platinum-free group (P = .004).Conclusion: Cisplatin-based treatment protocols were shown to worsen renal function during long-term follow-up. It is important to monitor kidney function closely for early intervention.