Abstract： Objective:To investigate the safety of incisions，perioperative indexes，and effect of hyperbaric oxygen（HBO）therapy combined with sinus tarsi approach in treating the closed calcaneal fracture.Methods:A total of 83 patients with closed calcaneal fracture admitted to the Second Naval Hospital of the Southern Theater Command from September 2019 to March 2022 were selected as the study subjects，and they were randomly divided into observation group（42 cases）and control group（41 cases），according to the random number table method. The observation group was treated with open reduction and internal fixation with steel plates and screws through the sinus tarsi approach，followed by HBO therapy postoperatively. The control group was treated with open reduction and internal fixation with steel plates and screws through extensile lateral approach. Perioperative indicators，reduction ability，and incidence of incision-related complications were compared between the two groups. One year after operation，the patients’ ankle and hindfoot function was evaluated using the Ankle-Hindfoot Scale of the American Orthopedic Foot and Ankle Society（AOFAS）.Results:The differences in surgical duration and fracture healing time between the two groups were not statistically significant（ P>0.05）. However，the waiting timing for surgery and length of hospital stay in the observation group were significantly lower than those in the control group（ P<0.01 or P<0.001）. The differences in the calcaneal height and Bohler angle between the two groups of patients were not statistically significant preoperatively，postoperatively，and upon fracture healed（ P>0.05）. Both calcaneal height and Bohler angle increased postoperatively and upon fracture healed compared with those before surgery，repectively（ P<0.05）. However，the calcaneal heights of both groups upon fracture healed were lower than those after surgery（ P<0.05）. The Bohler angle in the control group upon fracture healed was smaller than that after surgery（ P<0.05）. The incidence of incision-related complications in the observation group was significantly lower than that in the control group（ P<0.01）. After 1-year follow-up，the patients in the observation group showed better foot and ankle function compared with the control gruop（ P<0.05）. Conclusion:HBO therapy combined with sinus tarsi approach for closed calcaneal fractures can effectively restore the shape of the calcaneus and improve ankle and hindfoot function，shorten patients’ waiting time for surgery and hospital stay，and reduce the incidence of incision-related complications.