Abstract [Objective] To investigate the biomechanical properties of NICE knot in fixing the middle clavicle fracture [ Methods] 60 human clavicle specimens were randomly divided into 4 groups and the middle clavicle fracture model (OTA/AO type 15-A2) was made with orthopedic pendulum saw. The fixation methods of each group were: 1. Lag screw fixation; 2. NICE knot fixation with 2-0# size suture; 3. NICE knot fixation with 1-0# size suture; 4. NICE knot fixation with 1# size suture and each group was named as lag screw group, 2-0# group, 1-0#group and 1# group in turn. Failure load, maximum displacement and yield stiffness in different groups was tested by Instron biomechanical machine. [Results] After data analyses, there were no significant differences in failure load, maximum displacement and yield stiffness between group 1# and lag screw group (P > 0.05), but there were significant differences compared with groups 2-0# and 1-0# (P < 0.05). The biomechanical properties of group 1# were significantly better than those of groups 2-0# and 1-0#. [ Conclusion] The use of 1# sutures for NICE knot to fix the mid-clavicle fracture has the same biomechanical properties as the lag screw fixation, but has less adverse effect on blood flow around the fracture site. The NICE knot is easy to manipulate intraopeartively, and can be applied with locking compression plate for fixation of the mid-clavicle fracture.