An apparatus for catching byproducts in semiconductor device processing equipment is disposed in an exhaust line between a process chamber and a vacuum pump. The apparatus includes a cylindrical trap housing member, an upper cover and a lower cover covering the upper part and lower part of the trap housing, respectively, a heater disposed under the upper cover, first and second cooling plates disposed in the trap housing, a post spacing the cooling plates, apart and a cooling system for cooling respective portions of the apparatus. The cooling system includes a delivery pipe for supplying refrigerant, a discharge pipe for discharging the refrigerant from the apparatus, first cooling piping extending through each cooling plate and connected to the delivery and discharge pipes, and second cooling piping extending helically along the outer circumferential surface of the trap housing.