Abstract： Objective:To investigate the effect of hyperbaric oxygen adjuvant therapy in the postoperative treatment of the patients with emergency open tibiofibular fracture.Methods:A total of 97 patients with open tibiofibular fracture admitted to the Shanxi Bethune Hospital from October 2018 to October 2019，were randomly divided into control group（48 cases）and observation group（49 cases），according to the random table method. After operation，the control group was given conventional physical therapy，while the observation group was given hyperbaric oxygen adjuvant therapy on the basis of the conventional treatment. The therapeutic effect，serum alkaline phosphatase（AKP）level at different time points，and the incidence of complications of the two groups were compared.Results:The effective rate of the observation group（91.84%）was higher than that of the control group（81.25%），with statistically significant difference（ P<0.05）. Two to three weeks after operation，the serum AKP activities in both groups were high and reached the peak，and the AKP level of the observation group was significantly higher than that of the control group，with statistically significant difference（ P<0.05）. Four to six weeks after operation，the serum AKP activity of the observation group was significantly reduced，and it was lower than that of the control group，with statistically significant difference（ P<0.05）. Then the serum AKP level and activity of the observation group had continuously declined until at 12 weeks after operation when there was no significant difference between the two groups（ P>0.05）. The incidence of postoperative complication of the control group（27.08%）was higher than that of the observation group（8.16%），and the difference was statistically significant（ P<0.05）. Conclusion:Hyperbaric oxygen adjuvant therapy has a marked curative effect in the postoperative treatment of the patients with open tibiofibular fracture. It can significantly improve the activity of serum bone AKP and reduce the incidence of complication.