Background/Objectives: Intraoperative radiotherapy (IORT) has been used for decades to improve local control in advanced and recurrent head and neck cancers by delivering a concentrated dose of radiation directly to the tumor bed during surgery. Despite its potential advantages, IORT remains controversial due to its high complication rates and logistical complexity. This systematic review aims to assess the current evidence on IORT in head and neck oncology, evaluating its indications, effectiveness, and limitations. Methods: A systematic literature review was conducted in accordance with Cochrane systematic review method and reported following PRISMA guidelines. Databases, including Medline, Embase, Cochrane, and Web of Science, were searched for studies evaluating IORT in head and neck cancer. Outcomes of interest included local control rates, overall survival, complications, and treatment logistics. Data were weighted based on patient numbers, and statistical analyses included weighted means and comparative tests. Results: Included in this review are 47 studies that included 2330 patients. The studies were highly heterogeneous, limiting definitive conclusions. IORT was mainly used in stage III/IV or recurrent tumors, with an average dose of 14.7 Gy (range: 1–40 Gy). The five-year local control was 47% to 82%. Complication rates included wound necrosis (22,3%), fistulas 34 (17.8%), and carotid blow-out (14.5%). Logistical constraints remain a major limitation. Conclusions: The heterogeneous data and logistic challenges of IORT in head and neck oncology have limited its use, and the benefits remain uncertain.