While visceral adiposity and lipid dysregulation are established drivers of metabolic dysfunction-associated steatotic liver disease (MASLD), the clinical utility of the lipid accumulation product (LAP) for identifying prevalent MASLD in patients with type 2 diabetes mellitus (T2DM) remains insufficiently characterized. This study aimed to characterize the dose-response relationship between LAP and MASLD in T2DM, establish optimal sex-specific diagnostic thresholds, and evaluate its clinical net benefit to guide non-invasive screening.