Introduction & Objective: Free flaps are one of the procedures used to treat patients that need to plastic surgery. This study was performed to determine the complications of free flaps in patients in Hazrat-e-Fatemeh Hospital in five-year period since 2009 to 2014. Materials & Methods: In this observational study that was performed as a cross-sectional descriptive survey, 64 consecutive patients under free flap surgery in Hazrat-e-Fatemeh Hospital in five-year period since 2009 to 2014 were enrolled and the complications of free flaps and contributing factors were determined among them. Data were analyzed using SPSS software, version 19 and chi-square test and analysis of variance was used to express the results. Results: The findings from the study showed that in patients results in 53 patients (82.8%) was good; in 7 patients (10.9%) percent need repair due to partial necrosis in 2 patients (3.1%) required to remove the flap due to partial necrosis in 2 patients (3.1%) due to the need to remove the complete necrosis flap. Conclusions: According to the obtained results, it may be concluded that nearly 17 percent of patients under free flap surgery may experience some complications that cause to repair or removal flap which it would have no known contributing factors to be developed.