<p>This review provides a comprehensive analysis of phase-specific management strategies for type 2 diabetes (T2D) in patients undergoing gastric cancer (GC) surgery, encompassing the preoperative, intraoperative and postoperative phases within the context of oncodiabetology. In the preoperative phase, predicting T2D remission and evaluating antidiabetic medications while considering their adverse event profiles are important. These medications include metformin and sodium-glucose cotransporter 2 inhibitors, which may help prevent both T2D progression and GC advancement. Regarding surgical approaches, Roux-en-Y reconstructions are associated with better T2D remission rates than Billroth I/II reconstructions, likely because of enhanced glucose metabolism. The considerable effects of gastrectomy and reconstruction on glucose levels have led to the development of a new surgical approach, known as oncometabolic surgery. This approach integrates oncologic treatment with metabolic benefits and has gained attention as a promising strategy for managing T2D in patients undergoing GC surgery. In the postoperative phase, glucose monitoring, individualized medication adjustments, weight management, and patient education are essential for maintaining remission and preventing relapse. A comprehensive, stage-specific approach to glycemic care is crucial for improving both metabolic and oncologic outcomes in patients with GC.</p>