Microthrombosis may be involved in the pathogenesis of cardiac microangiopathy due to diabetes. Recent studies have shown that fibrinogen-like protein 2 (fgl2) plays a pivotal role in microthrombosis in viral hepatitis, acute vascular xenograft rejection and cytokine-induced fetal loss syndrome. The current study was designed to examine the expression of fgl2 in microvascular endothelial cells and investigate the effects of microthrombi due to fgl2 on cardiac function and structure in rats with type 2 diabetes. Following induction of type 2 diabetes, 24 rats were observed dynamically. Fgl2 expression and related cardiac microthrombosis were examined. Local or circulating TNF-α was measured. Coronary flow (CF) per min was calculated as an index of cardiac microcirculation. Cardiac function and morphology were evaluated. It was found that Fgl2 was highly expressed in cardiac microvascular endothelial cells of rats with type 2 diabetes, which was promoted by local or circulating TNF-α. The Fgl2 expression was associated with cardiac hyaline microthrombosis. In parallel with the fgl2 expression, CF per min, cardiac diastolic or systolic function and cardiac morphology were aggravated to some extent. It was concluded that in rats with type 2 diabetes, microthrombosis due to fgl2 contributes to the impairment of cardiac diastolic or systolic function and morphological changes.