Objective We aimed to evaluate the association of the severity of left ventricular (LV) diastolic dysfunction with long-term outcomes in patients with normal ejection fraction. Design Retrospective study. Setting A single centre in Japan. Participants We included 3576 patients who underwent both scheduled transthoracic echocardiography and ECG between 1 January and 31 December 2013, in a hospital-based population after excluding valvular diseases or low ejection fraction (14 (with relaxation disorder and high LV end-diastolic pressure, n=646). Primary and secondary outcome measures The primary outcome measure was a composite of all-cause death and major adverse cardiac events (MACE). The secondary outcome measure were all-cause death and MACE, separately. Results The cumulative 3-year incidences of the primary outcome measures were significantly higher in the e′14 group (23.4%) than those for the e′≥7 group (13.0%; p14 related to e′14 was associated with the long-term prognosis in patients with normal ejection fraction in an incremental fashion.