Open fractures are those exposed to the out side environment through a skin wound. Theyrnare at risk of complications such as infected non-union and other co-morbid conditions.rnSixty to seventy percent of compound fractures are believed to be contaminated withrnbacteria at the time of injury from both skin and environment. Infection of open fracturesrndepends on the microbial and host factors. In Ethiopia, a high incidence of open fracturernwound infection is suspected though the magnitude of the problem is not known. Norndocumented report on bacterial isolates from open fracture wounds and their drug resistancernpattern. During a period of November 2007 and May 2008, a cross-sectional prospectivernstudy was conducted to determine the bacteriology of open fracture wounds of 191 informedrnand consented patients who visited the orthopedic surgery department of Tikur AnbessarnUniversity Hospital, Addis Ababa, Ethiopia. The modified Gustilo and Anderson (G-A)rngrading of open fractures based on severity and extent of soft-tissue injury was used torncategorize the open fractures. The clinical features of the open fracture wounds werernassessed and wound swab specimens were collected using Levineâ€™s technique from eachrnpatient. All of the wound specimens were processed for microscopic examination, culturernand sensitivity testing. The causes of the fractures varied, but most of the open fracturesrnwere caused by car accidents (37.2%) and occurred in lower extremities bones (60.0%). Ofrnthe 191 patients, 82.7% were males and 17.3% were females (p < 0.05) resulting in anrnoverall male to female ratio of 4.8:1. The average age of the patients was 31.55 years (agernrange 4 to 75 years). According to G-A grading, 23.0% of the fractures were grade I; 41.5%rnwere grade II; 14.0% were grade IIIA; 5.5% were grade IIIB and 16.0% were grade IIIC. Ofrnthe 200 wound specimens examined by gram stain, 30.5% were positive for the presence ofrnbacteria. Out of the 200 wound specimens cultured, 82 (41%) were positive for bacteria. Ofrnthe culture-positive wounds, 51.2% showed mono-microbial growth and 48.8% showedrnpolymicrobial growth. In general, a total of 162 bacterial pathogens were isolated from thernopen fracture wounds sampled. Staphylococcus aureus was the dominant isolate (14.8%)rnfollowed by Acinetobacter spp. (11.4%). The gram-positive and gram-negative bacteriarnaccounted for 34.0% and 66.0%, respectively (p< 0.05). All gram-positive bacterial isolatesrnshowed low level of resistance (