In this study, increases in the moldability and interfacial adhesion strength according to the compatibility of different thermoplastic polypropylene polymer resin materials utilizing wood by-products produced by roadside tree pruning and changes in mechanical properties (impact strength ASTM D-256, tensile strength ASTM D-638, flexural modulus ASTM D-790) were verified. This study suggests the potential commercialization of wood composite materials from roadside tree pruning by-products of Platanus occidentalis L. based on compatibilizer treatment and the application of alkali and a silane coupling process. A new eco-friendly product group market is anticipated for use of this wood waste by-product, to reduce the use of limited petroleum resources, and to utilize ecofriendly cyclic-type resources.