The invention discloses a woven bag cutting off and bag opening separation flattening device. The woven bag cutting off and bag opening separation flattening device comprises a conveying platform (1)and is characterized in that mounting frames (2) are arranged on the two sides of the conveying platform (1), lower sliding grooves (9) are formed in the lower portions of the mounting frames (2), sliding pin shafts (7) are arranged in upper sliding grooves (8) and the lower sliding grooves (9), telescopic air cylinders (3) are arranged on the outer sides of the mounting frames (2), the telescopicends of the telescopic air cylinders (3) are hinged to one ends of upper connecting rods (5) and one ends of lower connecting rods (6) through hinge shafts (4), and the other ends of the upper connecting rods (5) are connected with sliding pin shafts (7) in the upper sliding grooves (8). The device is reasonable in structure, a mechanical device is used for achieving rapid bag rubbing separating,in the hot cutting process, rapid separating is achieved automatically, the blowing manner is used for further improving the separating effect, the bag rubbing separation operation of different angles can be carried out, and the automation degree is high.