Wetting is an important interface characteristic of wood-based material, which describes what happens when an adhesive comes into contact with a wood surface. In this study, a wetting model was developed to describe the dynamic contact angle process at the wood-based material surface. A parameter (K) was used to evaluate the wettability during the adhesive wetting process. By applying the wetting model, two resins (MDI) and (UF) wetting of median density straw board (MDSB) was studied. It was seen that the wetting model could accurately describe the dynamic adhesive wetting process on MDSB surface. The model analysis showed that MDI resin exhibited a better wettability on MDSB surface than UF resin did.