Purpose Left ventricular diastolic dysfunction is an independent risk factor for adverse cardiovascular morbidities and mortalities in cardiovascular and high-risk surgical patients. However, there were only a few investigations among intermediaterisk surgical patients. This study aimed to investigate postoperative heart failure (HF) in intermediate-risk surgical patients who had preoperative diastolic dysfunction with preserved ejection fraction (EF). Methods Consecutive patients underwent intermediate-risk surgery between January 2016 and December 2018 were retrospectively evaluated. Patients with preserved EF were divided into three groups using one of the parameters of diastolic function: the ratio of early diastolic filling velocity to the peak diastolic velocity of mitral medial annulus (E/e') ≥ 15, E/e' between 8 and 15, and E/e' < 8. Postoperative HF was defined as clinical symptoms and radiological evidence and low SpO 2 less than 93%. The primary outcome was the incidence of postoperative HF and its relation to preoperative E/e'. Chi-squared test, unpaired t test with Welch's correction, and multivariate logistic regression were used for analysis. Results In total, 965 patients were included in the final analysis. Postoperative HF developed in 36/965 (3.7%) patients with preserved EF. The incidence of postoperative HF was stratified according to the E/e', and the rates of HF occurrence in patients with E/e' < 8, 8-15, and ≥ 15 were 1.8%, 2.7%, and 15%, respectively (P < 0.01). Conclusion Preoperative elevated E/e' (≥ 15) was associated with the development of postoperative HF in intermediate-risk surgical patients with preserved EF.