Abstract: The present invention provides a method for depth removal of a volatile organic compound (VOC) in polymer resins and products thereof by means of a steam distillation method and apparatus thereof and significantly reducing the odor of the polymer resins and products thereof. The method provided in the present invention can further remove residual inorganic ash in the polymer resins. In the method, saturated steam at a certain temperature continuously keeps in contact with materials for a certain period of time, the VOC and an inorganic small molecule (ash) adsorbed on the surface of a polymer and wrapped inside the polymer are promoted to be enriched in a gas phase or a liquid phase and discharged, so as to reduce the VOC and ash in polymer materials, and the odor of the polymer resins or materials is decreased to a better level.