BACKGROUND The aim of this case report is to present an option of reconstruction in tumors involving the posterior wall and column of the acetabulum with sparing of the anterior column and the weight-bearing dome. METHODS We are reporting a case of a 25-year-old female with histopathologically proven synovial sarcoma involving the left inferior pubic ramus, ischium, and posterior wall of the acetabulum, along with a large soft-tissue extension in the posterior and medial thigh. Wide local excision involving partial acetabular resection and reconstruction using a femoral head allograft was carried out. The patient was allowed full weight-bearing mobilization after 6 weeks. At 3 months' follow-up, the patient was able to walk without support and was able to do active straight leg raising. There were no radiological signs of joint degeneration at the 12-month follow-up. CONCLUSIONS Reconstruction with non-articular femoral head allograft can be a viable alternative after resection of tumor involving acetabulum. This procedure is expected to support the hip joint and restore function in the short term and recreate bone stock for future arthroplasty if the need arises.