The invention relates to an oil expression device and belongs to the technical field of press machines specially suitable for special purposes. The oil expression device comprises a housing, wherein the housing is provided with a feeding port and a discharging port, the housing is provided with a feeding groove opposite to the feeding port, a motor, a rotating shaft and a rotary drum are sequentially arranged in the housing from left to right, one end of the rotating shaft is connected with the motor, the other end of the rotating shaft is connected with the rotary drum, a gear is coaxially connected to the rotating shaft, cutting teeth are further meshed with the upper portion of the gear, the feeding groove is provided with a connecting shaft and a spiral propelling mechanism, the connecting shaft is coaxially connected with the spiral propelling mechanism and the cutting teeth, a plurality of oil expression plates different in length are hinged to the rotary drum and are spirally arranged on the rotary drum from left to right and from long to short, and an oil outlet cylinder is further arranged in the housing, surrounds the rotary drum and is provided with a plurality of oil outlets. By adopting the scheme, the oil expression device is simple in structural operation, the vibration of the device is reduced, crude oil and oil residues are separated in the oil expression process, and the oil expression device is suitable for expression processing of a variety of crude oil to be expressed.