Objective To explore the clinical effect of suture anchor combined with open reduction internal fixation in the treatment of ankle joint fracture with triangular ligament injury.Methods A total of 40 patients hospitalized in our hospital from October 2012 to August 2016 who were diagnosed with ankle fracture complicated with deltoid ligament injury and treated with open reduction and internal fixation for fracture were selected and divided into the deltoid ligament repair group and the control group (unrepaired group), with 20 cases in each group. In the deltoid ligament repair group, suture anchors were used to repair the deltoid ligament. In the unrepaired group, no triangular ligament repair was performed during the operation, and the plaster were used after the operation. One year after surgery, X-ray examination was performed to measure the medial malleolar space at the gravity stress position of lower limbs, and the affected side was compared with the healthy side. At the same time, American Orthopaedic Association (AOFAS) foot and ankle scoring system was used to evaluate the surgical effect. Results Postoperative follow-up was 12 to 22 months (mean 14.5 months), and no complications occurred such as infection. The gravity stress position of medial malleolus space was (3.47±0.32) mm on the affected side and (3.44±0.35) mm on the healthy side in the triangular ligament repair group one year after surgery, and there was no statistical difference between the two sides (P＞0.05). While, the medial malleolus space in the unrepaired group was (3.74±0.34) mm on the affected side and (3.33±0.29) mm on the healthy side, and there were statistically significant differences between the two sides (P＜0.05). In the triangular ligament repair group, the AOFAS scores were excellent in 6 cases, good in 10 cases, fair in 2 cases, poor in 2 cases, and the overall excellent and good rate was 80%. While, in the unrepaired group, 4 cases were excellent, 7 cases were good, 5 cases were fair, and 4 cases were poor, the overall excellent and good rate was 55% Conclusion The triangular ligament plays an important role in the stability of the ankle joint. The application of anchors in the repair of the triangular ligament injury associated with ankle fracture is satisfactory. There was no significant widening of the medial malleolar space during the follow-up, while the medial malleolar space was significantly widened in the patients who did not repair the triangular ligament