Aim: Diabetic cardiomyopathy is a subset of heart disease that is directly associated with diabetes, and left ventricular diastolic dysfunction is the earliest sign. We aimed to investigate the association between sex differences and left ventricular diastolic function in patients with type 2 diabetes.Methods: This was a cross-sectional study included patients with type 2 diabetes who visit the National Metabolic Management Center (MMC) at the First People's Hospital of Yunnan from 2018 to 2021. Patients with hypertension, history of heart disease or ejection fraction <50% were excluded from the study. Logistic regression was used to analyze their associations.Results: A total of 1778 patients were included in the study. The study included 1205 (70%) males and 573 (30%) females. Compared with males, females had higher total cholesterol and LDL cholesterol levels but lower diastolic pressure, body mass index (BMI), visceral fat area, HbA1c, blood urea nitrogen (BUN), serum creatinine and triglyceride. Females had a relatively higher ejection fraction than males (68.17 & PLUSMN; 6.055 vs 67.5 & PLUSMN; 6.096, P < 0.05). More female patients than male patients in the age group of 45-60 years old had left ventricular diastolic dysfunction (female vs male, 54.5% vs 46.9%, P < 0.05). We also found that females were independently associated with left ventricular diastolic dysfunction, after adjusting for important clinical factors.Conclusion: Left ventricular diastolic function might be worse in female patients with type 2 diabetes. Further study is needed to verify the underlying mechanism.