BACKGROUND: The present study aimed to compare outcome of primary and secondary Illizarov''s fi xator application as a treatment method for type Ⅲ open tibial fractures in terms of non-union and wound infection.METHODS: This prospective study was done in a tertiary care center. Forty-eight type Ⅲ tibial fractures were treated with Illizarov''s apparatus between 2008 and 2011. The patients were divided into two groups depending on the treatment protocol, timing of wound closure and Illizarov''s application, primary (n=28) and secondary (n=20).RESULTS: In the primary group, healing was achieved in all 28 patients. The median time to recovery was 24 weeks, and the median number of operations was 3. There were 6 patients with a bone defect. In the secondary group, complete recovery was achieved in 18 out of 20 patients. The median time to recovery was 30 weeks, and the median number of operations 5. There were 9 patients with a bone defect. The median time to recovery and the number of operations were signifi cantly smaller in patients undergoing primary operation. Union was 100％ in the primary group and more than 95％ in the secondary group. Chronic osteomyelitis persisted in one patient and below amputation was done in one patient in the secondary group.CONCLUSION: Primary wound closure and Illizarov''s fixation required a smaller number of operations and shorter time to recovery than secondary wound closure and Illizarov''s fi xation, mostly due to a signifi cantly less number of patients with a bone defect in the primary group.