The utility model relates to a plastic section door frame which is composed of a door frame, a door seal, a pressing bar and a screw, wherein the door frame is a section which is enclosed into four hollow cavities by plane surfaces and inclined surfaces, a cruciform reinforcing rib is arranged in the door frame, wings and holes, which are used for installing conveniently, are arranged outside the door frame, the combined type door seal is matched with the door frame for decorating the door frame, so the door frame has the advantages of easy installation, practicality and beauty. The utility model has the advantages of reasonable section design, simpler structure, low cost, favorable sealing performance and good decorating effect. The utility model is suitable for installing doors or windows which have higher sealing requirement.