Polypropylene (PP) is the most widely used plastic resin in the world. This resin features excellent heat resistance, flexibility, surface quality, and dimensional stability. PP is used for various things around us in ordinary homes, such as home electronics appliances, car parts, toys, and sporting goods. However, it is difficult to mold a PP-only filament because of significant warpage and shrinkage. We compounded PP with glass wool (GW) and successfully developed a 3D printing filament with enhanced durability and dimensional stability.