This study aims to address the following key scientific question by establishing a large-scale, high-standard clinical cohort: the independent contribution of MASLD and its progression to liver fibrosis on cardiovascular outcomes in patients with T2DM, after excluding the confounding effects of traditional cardiovascular risk factors. Its technical value lies in utilizing prospective follow-up data combined with a multivariable competing risks model to develop and validate a cardiovascular risk prediction and early warning system tailored for Chinese populations with T2DM complicated by MASLD. Clinically, the findings will provide interdisciplinary evidence-based support for endocrinology and cardiology, helping clinicians identify high-risk individuals and prevent cardiovascular events through early intervention targeting hepatic metabolic disorders. This has significant implications for reducing overall mortality among diabetic patients in China and alleviating the public health burden.