The invention relates to a drying treatment system of slurry. The drying treatment system is characterized by comprising a slurry raw material storing warehouse, a scraper conveying machine, a prepared material cabin, a slurry drying machine, a coal dust gas dusting machine, a gas recycling device and a finished product storing warehouse. The inner wall of an overhaul door of the slurry drying machine in the treatment system is made of materials which are not apt to deform under high temperature and smooth in surface, so that the phenomenon of wall sticking of sticky materials is avoided. The inner wall and the outer wall of the overhaul door are separated from each other through thermal insulation materials, so that deformation of the outer wall and the inner wall is reduced to the minimum degree, and tightness of the overhaul door can be guaranteed. A set of electric actuator is introduced, and automation in opening and closing of the overhaul door can be achieved. The drying treatment system has the advantages of being low in energy consumption, low in noise, strong in structural stability, high in processing efficiency, low in device cost, strong in device adaptation, free of blocking, less in production failure, low in manufacture cost, and capable of saving resources.