The invention relates to the field of semiconductor processing, in particular to a semiconductor made thick photoresist film coating device and an application method thereof. The semiconductor made thick photoresist film coating device comprises an electric cylinder, spraying heads, a photoresist cup assembly, a rotary adsorption mechanism and a base plate. The electric cylinder and the photoresist cup assembly are both arranged on the base plate. A movable beam is arranged on the electric cylinder. The spraying heads spraying heads of which the intervals and the height can be all adjusted are arranged on the movable beam. The rotary adsorption mechanism is provided with a rotary adsorption disk used for adsorbing a wafer. The adsorption disk is arranged in the middle of the photoresist cup assembly. During photoresist film coating, the spraying heads are driven by the movable beam of the electric cylinder to move horizontally above the adsorption disk. The to-be-processed wafer is put on the adsorption disk. The multiple spraying heads are driven by the electric cylinder to move synchronously and horizontally and spraying photoresist, and then the wafer is fixedly adsorbed by the adsorption disk. The multiple spraying heads are driven by the electric cylinder to move synchronously and horizontally and spray the atomized photoresist. According to the semiconductor made thick photoresist film coating device and the application method thereof, even spraying is ensured, the film thickness of the whole wafer is made to be uniform, and edge protrusions of the wafer is avoided completely.