Objective To study the relationship between microalbuminuria and cardiac diastolic function in patients with type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD). Methods A total of 262 patients with T2DM and NAFLD were included in this study. Patients were divided into normal group (n=106) and abnormal group (n=156) according to their cardiac diastolic function. Data of waist circumference (WC), low density lipoprotein cholesterol (LDL-C), triglyceride(TG), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), fasting insulin level (FINS), insulin resistance index (HOMA-IR), glycosylated hemoglobin (HbA1c), glomerular filtration rate (GFR), C reactive protein (CRP), urinary microalbuminuria excretion rate (UAER), left ventricular myocardial quality index (LVWI) and liver fat content (LFC) were compared between two groups. All patients were divided into four groups according to data of UAER and GFR:group A[UAER<20μg/min and GFR≥90 mL/(min · 1.73 m2)], group B [UAER<20μg/min and GFR<90 mL/(min·1.73 m2)], group C [UAER≥20μg/min and GFR≥90 mL/(min·1.73 m2)], and group D [UAER≥20μg/min and GFR<90 mL/(min · 1.73 m2)]. The differences between the relevant indicators were analyzed between groups. Logistic regression analysis was used to compare UAER between normal group and abnormal group. Also the relationship between the related factors and cardiac diastolic function was compared between these two groups. Results For abnormal group, TG, SBP, HOMA-IR, CRP, UAER, LVWI and LFC were significantly higher, and GFR was significantly lower, than those of normal group (P<0.05). There were no significant differences in other indicators between two groups. Values of peak early/late diastolic filling velocity (E/A) showed a reduction trend in order in A, B,C and D groups (P<0.05). Values of LVWI showed a increasing trend in order in four groups (P<0.05). Values of LFC were significantly higher in C and D groups compared with those of A and B groups (P<0.05). There was no significant difference in LFC between A group and B group. The GFR<90 mL/(min·1.73 m2)was an independent risk factor for cardiac diastolic function in normal group of UAER, and higher UAER was an independent risk factor for cardiac diastolic function in the abnormal group of UAER. Conclusion There is obviously reduced cardiac diastolic function in patients with T2DM and NAFLD and microalbuminuria. When UAER≥20 μg/min, the higher UAER is an independent risk factor for reducing diastolic cardiac dysfunction.