The improved positioning device, for use in hip, pelvis or bariatric surgery, securely and safely supports a morbidly obese patient lying in the lateral decubitus position at one side of an operating table so the surgeon may stand close to the anterior side of the patient. The support device includes a double-ended bracket having a pair of oppositely positioned padded end portions secured to an angular bracket post adapted to securely mount to an operating table via a question mark-shaped bracket. The angular bracket arm vertically adjusts to support the patient on one side, with the padded end portions applied to bony prominences such as the symphysis pubis and the lower side anterior superior iliac spine. The support device is used in combination with a posterior pelvic support plate, and a pair of anterior-posterior chest support plates to retain the patient in a secure and stable manner during surgery.