In China Poplar wood-based panels mainly are used in non-structural field, but in the mechanical and electrical packaging industry use a lot of wood as a packaging material. Considering economic cost, resource utilization and environmental protection, an urgent need is for structural wood-based panels instead of wood as a mechanical and electrical packaging material. Shear Modulus for thick laminated veneer lumber in-plane is studied in this study, giving theoretically deduced and actual test to use the theory to guide practice. The purpose is to build a technology base of structural design, performance testing and use of laminated veneer lumber.