［Objective］ To study the biomechanical stability of the second generation dynamic anterior plate-screw system for quadrilateral area (DAPSQ) in treating anterior column and posterior hemi-transverse（ACPHT） acetabular fractures by using the finite element method. ［Methods］ Using finite element software to build the pelvis model of ACPHT acetabular fractures. And three groups of internal fixation models were respectively built: Group A was fixed by the second generation DAPSQ. Group B and Group C were respectively fixed by dual-column titanium plates and an anterior column titanium plate combined with a posterior column lag screw.Compare the stress distribution 、the average displacement of nodes on fracture lines and the stress shielding rate between groups under 600 N of physiological load imitating standing position. ［Results］The maximum stress exhibited a sequence of Group A（52.50MPa）>Group B(42.76 MPa)>Group C(37.69 MPa).The average displacement of nodes on fracture lines was ranked in the sequence of Group A0.05), while the difference between Group C and Group A or Group C and Group B were both statistically significant (P<0.05).［Conclusion］ The second generation DAPSQ has quite comparable biomechanical stability to dual-column titanium plates and is superior to an anterior column titanium plate combined with a posterior column lag screw in the treatment of ACPHT acetabular fractures.