PURPOSE: Free tissue transfer is a treatment option for soft tissue defects of the lower extremity. For a successful outcome, it is necessary to evaluate the vessel condition and blood flow patency. The administration of a vasopressor could impact the survival rate of free tissue transfer; however, there is a lack of studies on vasopressor use and lower extremity reconstruction. This study aimed to investigate the relationship between the use of a vasopressor and outcomes of free tissue transfer in lower extremity reconstruction. METHODS: This retrospective, observational study was conducted between March 2010 and February 2019. Data were divided into intraoperative and postoperative variables according to the administration time. Data on patient demographics, risk factors, details of reconstruction, flap outcomes, and duration of intensive care unit (ICU) stay were obtained. Binary logistic regression models were computed to determine the association between flap outcome and vasopressor administration. RESULTS: Of the 338 patients, 186 were administered a vasopressor. Intraoperative and postoperative vasopressor use was not related to the overall complication rate (odds ratio, 1.547; 95% confidence interval, 0.830-2.882; p = .169). Low-intraoperative levels of hemoglobin were associated with the overall complication rate. Postoperative vasopressor administration was associated with prolonged ICU stay. CONCLUSION: Our results showed that the intraoperative and postoperative use of vasopressors was not significantly associated with the success rate of free flaps. Future studies investigating the relationship between the dose, type, and duration of vasopressors and the complication rate following free tissue transfer are warranted.