This study was undertaken to evaluate the clinical course of isolated left ventricular noncompaction (ILVNC) and to identify the predictors for adverse outcomes in an adult cohort with ILVNC. Between March 2003 and April 2012, 106 adult patients diagnosed with ILVNC at Fuwai Hospital were included in this study. The medical history, electrocardiograms, and echocardiograms of these patients were retrospectively analyzed by chart review. Of these patients, 64 (60 %) were in New York Heart Association (NYHA) functional class III/IV and 84 (79 %) had systolic dysfunction (left ventricular ejection fraction (LVEF) <50 %). During a follow-up of 2.9 ± 2.1 years, 28 (26 %) patients died or underwent heart transplantation. The annual incidence of death or transplantation was 9.1 %. The determinants of death or heart transplantation included NYHA functional class III/IV (hazard ratio (HR) 4.52; 95 % confidence interval (CI) 1.57–13.04; P = 0.005), decreased left ventricular ejection fraction (HR 0.94; 95 % CI 0.90–0.97; P = 0.001), dilated left ventricular end-diastolic diameter (HR, 1.06; 95 % CI, 1.02–1.09; P = 0.001), increased left atrial diameter (HR 1.08; 95 % CI 1.03–1.14; P = 0.001), reduced systolic blood pressure (HR 0.96; 95 % CI 0.94–0.99; P = 0.003), the presence of pulmonary hypertension (HR 3.50; 95 % CI 1.63–7.51; P = 0.001), and right bundle branch block (HR 7.79; 95 % CI 2.56–23.76; P < 0.001). In conclusion, this study demonstrates that ILVNC is related to a high incidence of death or heart transplantation. Advanced heart failure, a dilated left heart with systolic dysfunction, reduced systolic blood pressure, pulmonary hypertension, and right bundle branch block predict adverse outcomes of ILVNC.