Objective To investigate the clinical efficacy of nickel titanium alloy embracing fixator in the treatment of flail chest and its effect on hemodynamics. Methods A total of 68 patients with flail chest who were admitted to the First Affiliated Hospital of Harbin Medical University from Sep. 2010 to Oct. 2015 were enrolled in this study. The patients were divided into control group and observation group according to different treatment methods, with 34 cases in each group. Patients in the control group received conservative treatment of thoracic band external fixation, and those in the observation group received operative treatment with nickel titanium alloy embracing fixator; both groups were followed up until Oct. 2016. The hospital stay, duration of mechanical ventilation, drainage tube indwelling time, intensive care unit (ICU) observation time, post-treatment pain, dosage of analgesics, hemodynamics, pulmonary function 1 month after surgery, complications and mortality of patients were compared between the two groups. Results Compared with the control group, the average hospital stay, duration of mechanical ventilation, drainage tube indwelling time and ICU observation time of patients were significantly shorter in the observation group (all P<0.05), and the Visual Analogue Scale score and dosage of analgesics were significantly lower (both P<0.05). The hemodynamic indexes such as cardiac index (CI), central venous pressure (CVP) and extravascular lung water index (ELWI) at 24 h and 48 h after treatment were significantly higher than those before treatment in both groups (all P<0.05). The CI and ELWI in the observation group were significantly lower than those in the control group at 24 h and 48 h after treatment (both P<0.05), while the CVP in the observation group was significantly higher (P<0.05). The vital capacity (VC) and the ratio of forced vital capacity (FVC) in one second to FVC (FEV₁/FVC) in the observation group were significantly higher than those in the control group (both P<0.05), while there were no significant differences in maximal mid-expiratory flow and peak expiratory flow rate between the two groups (both P>0.05). The overall incidence of complications in the observation group was significantly lower than that in the control group (47.1%[16/34] vs 17.6%[6/34], P<0.05), and the mortality was significantly lower than that in the control group (2.9%[1/34] vs 17.6%[6/34], P<0.05). Conclusion Nickel titanium alloy embracing fixator is a safe and effective method in the treatment of flail chest with less trauma, quick recovery, low incidence of complications, and can improve hemodynamics and reduce pain of patients.