Background: Metastatic clear-cell renal cell carcinoma (RCC) is largely incurable, and its treatment remains challenging. Sunitinib, a tyrosine kinase inhibitor, is one of the current standard-of-care options for treatment-naïve patients with metastatic RCC. Despite the proven efficacy of sunitinib, prolonged treatment with some tyrosine kinase inhibitors (TKIs) has been associated with significant adverse events (AEs). Therefore, we aimed to calculate the exact prevalence of all sunitinib-related AEs in a pooled analysis from all available randomized controlled trials (RCTs). Methods: A comprehensive electronic database search was conducted for all RCTs comparing the clinical outcomes and adverse events of sunitinib versus all other available treatments for treatment-naïve advanced/metastatic clear-cell renal cell carcinoma. We then calculated the pooled prevalence of the most common reported side effects of sunitinib. All statistical analyses were performed using R Statistical Software v3.4.0 (R Foundation, Vienna, Austria). Results: We included 8 RCTs, with a total of 4,106 patients. The mean age was 62, with 66.44% males. Any grade AEs were reported in 72% of patients with the following frequencies: fatigue, 44%; diarrhea, 38%; nausea, 31%; hand-foot syndrome, 30%; hypertension, 27%; dysgeusia, 25%; hypothyroidism, 25%; cconstipation, 20%; stomatitis, 20%; inflammation of the mucosa, 18%; dyspepsia, 16%; vomiting, 14%; rash, 12%; asthenia, 11%; and epistaxis, 10%. Grade 3 (severe) AEs were reported in 52% of patients with the following frequencies: hypertension, 9%; fatigue, 8%; hand-foot syndrome, 5%; asthenia, 5%; diarrhea, 4%; and inflammation of the mucosa, 2%. Laboratory abnormalities were also reported as follows: increased AST, 7%; increased lipase, 6%; neutropenia, 6%; thrombocytopenia, 6%; hypophosphatemia, 5%; lymphocytopenia, 5%; anemia, 4%; and leukopenia, 3%. Conclusion: Despite sunitinib being one of the current standard treatments for patients with metastatic/advanced clear-cell RCC, its safety profile is concerning, with a high prevalence of reported dangerous side effects. These findings underscore the importance of the emergence of newer drugs and treatment plans for patients with metastatic RCC, not only to achieve similar or better clinical outcomes but also to decrease the burden of adverse events.