Background: The change of left ventricular function deteriorated with age because of gradual increases of blood pressure may result in increased energy loss (EL) in left ventricle (LV). The present study investigated EL in LV among hypertensive elderly patients and examined factors contributing to EL. Methods: A single-center retrospective study was performed on elderly hypertensive outpatients (65 years) who underwent echocardiography (N=105). EL in the LV was measured using an vector flow mapping system, and factors affecting peak EL during the early diastolic phase (ED-EL), late diastolic phase (LD-EL), and systolic phase (Sys-EL) were evaluated. Result: Mean age was 79.9±6.4 years (male 43%). Mean ED-EL, LD-EL, and Sys-EL were 42.1±46.7, 75.6±60.2, and 40.4±40.2 mJ/N/s. In a stepwise regression analysis, the E wave peak velocity of transmitral flow (unstandardized B=0.002, 95%CI 0.001 to 0.002, standardized β=0.547, p<0.001) and stroke volume in the LV outflow tract (LVOT) (B=0.001, 95%CI 0.000 to 0.001, β=0.190, p=0.034) were identified as factors affecting ED-EL. The factors affecting LD-EL were the E/A ratio (B=-0.122, 95%CI -0.180 to -0.064, β=-0.451, p<0.001) and peak velocity in LVOT (unstandardized B=0.001, 95%CI 0.0001 to 0.001, β=0.339, p=0.003). The factors influencing Sys-EL were peak velocity in LVOT (B=0.001, 95%CI 0.001 to 0.001, β=0.619, p<0.001) and the E/A ratio (B=-0.050, 95%CI -0.087 to -0.013, β=-0.241, p=0.008). Conclusion: Peak EL in the LV was higher during diastolic phase than systolic phase among elderly hypertensive patients. Peak EL during each phase was affected by systolic blood flow in LVOT and LV transmitral flow.