Objective To measure and compare the insertion torque and pullout strength of newly-designed expansivespinal fixation system(ESS) pedicle screws with those of CD-II and GSS pedicle screws in normal human cadaververtebrae, and to evaluate the screw purchase of ESS pedicle screws. Methods Thirty lumbar vertebral bodiesobtained from 6 fresh normal male cadavers were classified into 3 groups randomly, 20 pedicles per group. ESS, CD-￠?,and GSS pedicle screws were implanted into the pedicles of each group respectively. The 34 last screw circles of eachpedicle screw were remained. The remained screw circles were implanted by using a material-testing machine (SWD-10,Changchun, China) to measure the insertion torque. Then each screw was extracted axially from the pedicle at a rate of5mm/min until failure by using the same machine. Force data were recorded and analyzed using a one-way ANOVA andLSD. P<0.05 was considered significant. Results The torques of the ESS, CD-II, and GSS screws were (5.79±1.85)Nm, (5.19? ?0.75)Nm, and (5.56±1.31)Nm respectively. The pullout strength of the ESS, CD-II, and GSS were (2219.80±367.60)N, (1630.65±392.58)N, and (1963.75±403.68)N respectively. The maximum axial pullout strength of ESS wasgreater than that of CD-II and GSS screws. The pullout strength difference was very significant between ESS and CD-II (P<0.001), was significant between ESS and GSS (p<0.05). Insertion torque was correlated positively with pulloutstrength between the ESS and CD-II pedicle screws (p<0.01). Conclusions ESS pedicles screws have good purchaseability, better than that of CD-II and GSS pedicle screws.