Background: Nephrectomy is one of the primary treatments of Stage I-III renal cell carcinoma (RCC), which is usually associated with low rates of serious morbidity and mortality. However, a fraction of patients gets readmitted after the surgery for numerous reasons which can impact their overall prognosis. Methods: We conducted a retrospective cohort study using the 2017 National Readmission Database of adult patients with RCC readmitted within 30 days after an index admission for nephrectomy. We aimed to identify the 30-day readmission rate, mortality, resource utilization, and independent predictors of readmission. Results: A total of 25,307 patients with RCC underwent nephrectomy. The 30-day readmission rate was 8.7%. The top five causes for readmission were sepsis, AKI, STEMI, surgical infections & metastatic disease. Patients requiring readmission were less likely to be discharged home (56.5 vs 81.8%), have private insurance (27.2 vs 34.7), obesity (14.7 vs 20.6%), hypertension (30.9 vs 47.1%), and be admitted to a teaching hospital (75.8 vs 79.2%). They were more likely to be insured with Medicare (58.3 vs 53.3%), have lower income (28.7 vs 26.3%), type 2 diabetes (32.4 vs 26.7%), CKD (44.1 vs 20.7%), malnutrition (9.2 vs 2.1%), undergo chemotherapy (5.2 vs 1.9%). Readmission was associated with higher in-hospital mortality (1.5 vs. 0.1%), CVA (0.6 vs 0.3%), AKI (29.6 vs 16.9%) and pleural effusion (7.8 vs 1.8%). They were also more likely to require mechanical ventilation (3.5 vs 1.8%), parenteral nutrition (1.2 vs 0.4%) and hemodialysis (11.9 vs 4.5%). The in-hospital economic burden of readmission was $128 million in total charges and $31.8 million in total costs. Independent predictors of readmission were disposition to a short-term hospital or skilled nursing facility, length of stay, need for mechanical ventilation and transfusion of blood products, having type 1 diabetes, malnutrition, pleural effusion, and CKD. Younger age and private insurance were associated with preventing readmission. Conclusions: Readmissions after nephrectomy in patients with RCC are associated with increased in-hospital mortality rate and pose a high health care economic burden. We identified few risk factors and patient characteristics associated with post-surgical readmissions; however, further in-depth studies are needed to find preventable risk factors.