Despite a generally high specificity, electrocardiographic (ECG) criteria for the detection of left ventricular hypertrophy (LVH) lack sensitivity, particularly in obesity patients. The aim of the study was to evaluate the accuracy of the most commonly used ECG criteria (Cornell voltage and Sokolow-Lyon index), the recently introduced Peguero-Lo Presti criteria and the correction of these criteria by body mass index (BMI) to detect LVH in obesity patients and to propose adjusted ECG criteria with optimal accuracy. The accuracy of the ECG criteria for the detection of LVH was retrospectively tested in a cohort of obesity patients referred for a transthoracic echocardiogram based on clinical grounds (test cohort, n = 167). Adjusted ECG criteria with optimal sensitivity for the detection of LVH were developed. Subsequently, the value of these criteria was prospectively tested in an obese population without known cardiovascular disease (validation cohort, n = 100). Established ECG criteria had a poor sensitivity in obesity patients in both the test cohort and the validation cohort. The adjusted criteria showed improved sensitivity, with optimal values for males using the Cornell voltage corrected for BMI, (RaVL+SV3)*BMI ≥700 mm*kg/m2 ; sensitivity 47% test cohort, 40% validation cohort; for females, the Sokolow-Lyon index corrected for BMI, (SV1 + RV5/RV6)*BMI ≥885 mm*kg/m2 ; sensitivity 26% test cohort, 23% validation cohort. Established ECG criteria for the detection of LVH lack sufficient sensitivity in obesity patients. We propose new criteria for the detection of LVH in obesity patients with improved sensitivity, approaching known sensitivity of the most commonly used ECG criteria in lean subjects. © 2020 The Authors. Clinical Cardiology published by Wiley Periodicals, Inc.