Purpose: This meta-analysis summarizes the incidence of treatment-related adverse events (AE) of BRAFi and MEKi. Methods: A systematic search of Medline/PubMed was conducted to identify suitable articles published in English up to 31 December 2021. The primary outcomes were profiles for all-grade and grade 3 or higher treatment-related AEs, and the analysis of single side effects belonging to both categories. Results: The overall incidence of treatment-related all-grade Aes was 99% for Encorafenib (95% CI: 0.97–1.00) and 97% for Trametinib (95% CI: 0.92–0.99; I² = 66%) and Binimetinib (95% CI: 0.94–0.99; I² = 0%). In combined therapies, the rate was 98% for both Vemurafenib + Cobimetinib (95% CI: 0.96–0.99; I² = 77%) and Encorafenib + Binimetinib (95% CI: 0.96–1.00). Grade 3 or higher adverse events were reported in 69% of cases for Binimetinib (95% CI: 0.50–0.84; I² = 71%), 68% for Encorafenib (95% CI: 0.61–0.74), and 72% for Vemurafenib + Cobimetinib (95% CI: 0.65–0.79; I² = 84%). The most common grade 1–2 AEs were pyrexia (43%) and fatigue (28%) for Dabrafenib + Trametinib and diarrhea for both Vemurafenib + Cobimetinib (52%) and Encorafenib + Binimetinib (34%). The most common AEs of grade 3 or higher were pyrexia, rash, and hypertension for Dabrafenib + Trametinib (6%), rash and hypertension for Encorafenib + Binimetinib (6%), and increased AST and ALT for Vemurafenib + Cobimetinib (10%). Conclusions: Our study provides comprehensive data on treatment-related adverse events of BRAFi and MEKi combination therapies, showing related toxicity profiles to offer a helpful tool for clinicians in the choice of therapy.