The invention provides a hydrocyclone. The hydrocyclone comprises a cylindrical barrel (2) and an abrasion-resisting conical barrel liner (6). The bottom end of the cylindrical barrel (2) is fixedly connected with the upper end of a conical barrel (3) through a flange, and the lower end of the conical barrel (3) is connected with a bottom flow pipe (5). A horizontal feeding pipe (1) is arranged on the upper portion of the side wall of the cylindrical barrel (2). The feeding pipe (1) is matched with the cylindrical barrel (2) in a tangential manner. A cover plate is arranged at the upper end of the cylindrical barrel (2). An overflow pipe (4) is arranged in the center of the cover plate. The abrasion-resisting conical barrel liner (6) is fixedly arranged on the lower region of the inner side of the conical barrel (3). The external diameter of the upper big-bore end of the abrasion-resisting conical barrel liner (6) is matched with the internal diameter of the corresponding region on the lower portion of the conical barrel (3), and the external diameter of the lower small-bore end of the abrasion-resisting conical barrel liner (6) does not make contact with the inner wall of the cylindrical barrel (2). According to the hydrocyclone, the service life of the bottom flow pipe of the hydrocyclone can be prolonged, and the maintaining cost can be reduced.