Background: Platelet dysfunction is implicated in the pathogenesis of diabetic complications. This study investigated the potential of platelet indices as predictive markers for complications in type 2 diabetes mellitus (T2DM). Methods: In this prospective observational study, 95 T2DM patients were followed for one year. Platelet indices, including Mean Platelet Volume (MPV), Platelet Distribution Width (PDW), and Plateletcrit (PCT), were measured at baseline and every three months. The development of microvascular and macrovascular complications was monitored. Results: Significant increases in all platelet indices were observed over the study period (p < 0.05). MPV showed the strongest correlation with HbA1c (r = 0.42, p < 0.01). ROC curve analysis revealed that MPV had the highest predictive value for both microvascular (AUC 0.76, p < 0.001) and macrovascular complications (AUC 0.79, p < 0.001). In multivariate analysis, MPV was an independent predictor of microvascular (OR 1.82, 95% CI 1.35-2.45, p < 0.01) and macrovascular complications (OR 2.13, 95% CI 1.56-2.91, p < 0.01). Conclusion: Platelet indices, particularly MPV, show promise as predictive markers for complications in T2DM, with a slightly stronger association with macrovascular complications. These findings suggest that platelet indices could potentially enhance risk stratification in diabetic patients