Objective To investigate the effects of preoperative calcaneal traction versus plaster splint fixation on the prognosis of unstable ankle fractures. Methods Patients with unstable ankle fractures admitted to the first People’s Hospital of Shuangliu District / West China (Airport) Hospital Sichuan University between April 2021 and March 2023 were selected. The enrolled patients were randomly divided into the experimental group (calcaneal traction fixation) and the control group (plaster splint) by using a random number table method. The preoperative waiting time, surgical duration, intraoperative blood loss, number of complications, fracture healing time, length of hospital stay, total hospitalization costs, and American Orthopaedic Foot and Ankle Society scores for the ankle joint were compared between the two groups. Results A total of 100 patients were included. Among them, there were 48 cases in the experimental group and 52 cases in the control group. There was no statistically significant difference between the two groups in terms of gender, age, and Denis-Weber typing (P>0.05). The patients were followed up for 12-26 months, with an average of (18.6±4.5) months. All ankle fractures clinically healed. The experimental group reported two cases of post-traumatic arthritis; the control group had one case of post-traumatic arthritis, one case of preoperative tension blisters with epidermal necrosis, and one case of superficial infection at the surgical incision postoperatively. The preoperative waiting time in the experimental group was significantly shorter than that of the control group [(7.35±3.23) vs. (10.04±5.34) days; P<0.05]. There was no statistically significant difference in the surgical duration, intraoperative blood loss, clinical fracture healing time, length of hospital stay, and total hospitalization costs between the two groups (P>0.05). Additionally, American Orthopaedic Foot and Ankle Society scores at postoperative months 1, 3, 6, 12, and at the last follow-up showed no significant differences between the two groups (P>0.05). Conclusions In conclusion, for unstable ankle fractures, there is no significant difference in clinical efficacy between preoperative calcaneal traction and plaster splint fixation. Calcaneal traction may reduce preoperative waiting time and lower the risk of soft tissue complications.