Background <p>While curved intertrochanteric varus osteotomy is an effective treatment for osteonecrosis of the femoral head, whether this procedure is applicable to bilateral cases remains unclear. The aim of this study was to compare the clinical outcomes of bilateral curved intertrochanteric varus osteotomy and unilateral curved intertrochanteric varus osteotomy for osteonecrosis of the femoral head.</p> Methods <p>This comparative study included 60 patients with osteonecrosis of the femoral head; 15 (30 hips) underwent bilateral curved intertrochanteric varus osteotomy (bilateral group) and 45 (45 hips) underwent unilateral curved intertrochanteric varus osteotomy (unilateral group). Patients in the bilateral group were followed up for a mean of 8.0&#xa0;years, whereas those in the unilateral group were followed-up for a mean of 8.2&#xa0;years. The Harris Hip Score, complication rates, radiographic parameters, and survival rates were assessed. Conversion to total hip arthroplasty and radiographic failure were the endpoints.</p> Results <p>The postoperative Harris Hip Score was significantly lower in the bilateral group than in the unilateral group. Complication rates and radiographic parameters were not significantly different between the groups. Ten-year survival rates, with conversion to total hip arthroplasty and radiographic failure as endpoints, did not differ significantly between the groups. In bilateral curved intertrochanteric varus osteotomy, the survival rate, with radiographic failure as the endpoint, tended to be poorer on the contralateral side than on the initial side.</p> Conclusion <p>The clinical outcomes of bilateral curved intertrochanteric varus osteotomy were not necessarily favorable. When planning for bilateral curved intertrochanteric varus osteotomy, surgeons should ensure that the contralateral hip could undergo surgical intervention timeously.</p>