Objective To observe biomechanical characteristics and advantages of the self-developed anatomical locking plate of sternoclavicular joint by comparison with the radial distal oblique T-shaped locking plate and sternoclavicular hook plate. Methods Nine embalming and moistening adult corpses were selected, including 6 males and 3 females. Model of complete dislocation of the sternoclavicular joint caused by complete removal of the sternoclavicular joint specimen. The bilateral sternoclavicular joints of 9 specimen models were randomly numbered, matched and divided into Group A(experimental group, sternoclavicular joint anatomical locking plate), Group B(control group 1, the radial distal oblique T-shaped locking plate) and Group C(control group 2, sternoclavicular hook plate), with 6 sternoclavicular joints in each group. All specimens were placed with steel plates on both sides and fixed on the universal mechanical test machine. Three biomechanical experiments were carried out, including loading of distal clavicle, torsion of distal clavicle and anti-pull out of sternum handle screw. Results Distal clavicle loading test: the load-displacement of specimens in three groups showed a linear relationship. The compressive deformation resistance in experimental group was stronger than that in two control groups. Distal clavicle torsion test: the relationship between torque and torsion angle was linear. The torsional deformation resistance in experimental group was stronger than that in two control groups. Anti-pullout test of sternum handle screw: there was a significant difference in the maximum anti-pullout force of sternum handle screw among the three groups (P＜0.05). The anti-pullout performance of the sternum handle screw in the experimental group was better than that in the two control groups. Conclusions The self-developed sternoclavicular joint anatomical locking plate is superior to the oblique T-shaped locking plate of distal radius and the plate of sternoclavicular hook in terms of anti-compression, anti-torsion and anti-pullout of sternoclavicular screw, so as to provide an ideal internal fixation device for the treatment of fracture and dislocation of sternoclavicular joint.