The paper analyzes the interaction between woven fabric and needle in the integrated piercing process of orthogonal laminated woven fabrics, proposes and establishes fiber bending elongation and elongation breakage model, and talks over the structure parameters influencing fiber bending elongation. Through theory analysis and testing result analysis, the paper indicates that breakage caused by bending and elongation around needles is a function of the ratio X between diameter of needle in Z direction and needles distance in Z direction, and suggests that smaller X value be chosen in order to reduce fiber elongation breakage of the integrated piercing.