Plastic drainage board is three-dimensional anti-extrusion or blow molding method using the production of high-density polyethylene (HDPE) geomembrane, the geomembrane by a special process on a closed-pressure cylindrical protruding, semi-conical, hemispherical shell, the formation of a membrane, a continuous shell, with three-dimensional space and some support stiffness, liquid, gas can flow in the excretion of the plate. This is a potential function of many functional materials, the use of this plate can easily build a elevated level, the use of overhead to form the drainage layer, the exhaust channel, the same elevated level to the use of noise, vibration function; Plastic drainage protection board in the field of civil construction works can be widely used in building roof system layer overhead, planted roof drainage ventilation, drainage construction basement waterproofing system protection, thermal insulation to protect interior surface of the moisture, road and rail tunnel drainage water and so on.