Acetabular reconstructive surgery is a good alternative method to treat acetabular fractures. The aims of this study were to assess the incidence, clinical pattern, and the relationship between various factors and heterotopic ossification (HO). This was a retrospective study involving all cases of acetabular fractures that underwent reconstructive surgery at Khartoum North Teaching Hospital in Khartoum state during the study period, (December 2006 to December 2011). A total of 132 patients with acetabular fractures were reviewed. The complete preoperative and post-operative data, together with information on regular follow up visits at 3 months, 6months and 2 years for each patient were collected. The SPSS was used for data processing. The male to female ratio was 4.3:1. Of the 132 cases 13 (9.8%) of them developed heterotopic ossification as a complication of the surgery. This consisted of 12 (92.3%) male and 1 (7.7%) female patients. The age range of the patients was 26-50 years. Road Traffic Accidents (RTA) /occupant constitute the most common mode of trauma 46.2%. AO (Arbeitsgemeinschaftfür Osteosynthesefragen foundation fracture classification) class A1 and B1 were the commonest types associated with HO. The mean hospital stay was 14 days. Male patients over 25 years of age with posterior hip dislocation, class A1 or A2, treated by posterior approach, were the highest at risk of developing Heterotopic Ossification.