Diabetes mellitus is a prevalent cardiovascular risk factor and is associated with higher rates of cardiovascular disease and mortality. Myocardial work (MW) is a novel echocardiographic measure of left ventricular (LV) function which allows for characterisation of cardiac energy expenditure and utilisation based on pressure-strain measurement. We sought to evaluate the prognostic utility of MW in patients with diabetes mellitus without established cardiovascular disease. Diabetic patients without established cardiovascular disease referred to our institution for stress echocardiography from Jan 2016 to Dec 2019 were prospectively recruited. Patients underwent a clinical assessment, resting and exercise stress echocardiography. Included patients were followed for up to five years for the composite endpoints of cardiovascular death and major adverse cardiovascular events (MACE). 85 diabetic patients (66.22±12.67yrs; 55% male) were recruited. 94% had hypertension and 55% had hypercholesterolaemia. Over the mean follow-up period of 36.88±22.28months, 10 patients developed the composite endpoint. These patients had lower left ventricular (LV) global longitudinal strain, higher global wasted work (GWW, p<0.01) and lower global work efficiency (GWE, p<0.01). Unadjusted Cox-regression showed GWW (p<0.01) and GWE (p<0.01) to be associated with adverse cardiovascular outcomes. Other factors associated with the composite outcome included LV indexed mass (p=0.02) and resting systolic blood pressure (p=0.03). In diabetic patients without established cardiovascular disease, increased GWW and reduced GWE were associated with poor cardiovascular outcomes. MW indices may help identify diabetic patients at risk of adverse cardiovascular events.