Objective To compare the stiffness, pull-out strength and energy absorption of two different sacroiliac screw fixation techniques under different loading conditions to determine the new fixation method more congruous with human biomechanics requirements. Methods Eight bone specimens of human pelvis of 23 to 45 year-old were used. No deformity, osteoporosis, tumor or trauma was found in all the specimens after gross anatomy, X-ray and BMD (bone material density) inspection. The eight pelvis were cut into halves and divided into two groups. Sixteen sacroiliac screws by using LX method were inserted into the left sides (Group one), the negative stress sacroiliac screw was inserted into the tension band of sacroiliac complex, the positive stress sacroiliac screw was inserted into the compression band. Eight ordinary sacroiliac screws were inserted into the right sides (Group two). The insertion torque, pull-out strength, relative migration, energy absorption ofeach screw were measured. Results The pull-out strength of the sacroiliac screws using LX method were higher than that of the ordinary sacroiliac screw (P<0.05). There exist obviously positive correlations between the insertion torque and the pull-out strength, the BMD and the pull-out strength, the BMD and the insertion torque (P<0.05). The energy absorption of the ordinary sacroiliac screws was higher than that of the pressure screws and the tension screws (P<0.05), but the total energy absorption was higher in the sacroiliac screws using LX method when compared with that of the ordinary sacroiliac screws (P<0.05). Conclusion The stiffness, pull-out strength and absorption energy of sacroiliac screws using LX method were biomechanically superior to that of ordinary sacroiliac screw. Therefore, the new sacroiliac screws fixation technique which is more congruous with human biomechanics requirements would be recommended for better stability of the reconstructed pelvis.