Objective To discuss the short-term effectiveness of total hip arthroplasty (THA) for post-traumatic osteoarthritis secondary to acetabular fracture. Methods Between January 2004 and March 2012, the clinical data was analyzed retrospectively from 12 cases (13 hips) of post-traumatic osteoarthritis secondary to acetabular fracture undergoing THA. Of 12 patients, 6 were male and 6 were female, with an average age of 55.6 years (range, 40-68 years). The locations were the left hip in 5 cases, the right hip in 6 cases, and bilateral hips in 1 case. The interval between acetabular fracture and THA was 65.7 months on average (range, 12-240 months). The preoperative hip Harris score was 48.8 ± 9.5. Results The incisions healed by first intention. No deep vein thrombosis and infection occurred postoperatively. Ten cases were followed up 1-7 years (mean, 4.8 years). The hip Harris score was 86.5 ± 8.6 at last follow-up, showing significant difference when compared with preoperative score (t=10.520, P=0.006). X-ray films showed no acetabular prosthesis instability. Stem subsidence (2 mm) occurred in 1 case, peri-prosthetic osteolysis in 2 cases, and heterotopic ossification in 2 cases (Brooker type I and type II in 1 case, respectively). Conclusion THA has satisfactory short-term effectiveness for post-traumatic osteoarthritis secondary to acetabular fracture. The good effectiveness is based on strict case selection, pathological evaluation, and the proper acetabular reconstruction.