A sorting device that sorts a specific material type matter and another material type matter from sorting objects, the sorting device comprising: a conveyor that conveys the sorting objects in a placed state in one direction, the sorting objects having the specific material type matter and the other material type matter other than the specific material type matter mixed, and causes the sorting objects to fly at a forefront portion of the conveyor; an identification part that identifies composition of the specific material type matter placed on the conveyor; an air blower (6, 10) that generates an airflow in a flying-out direction of the sorting objects; an upper rectifying plate disposed along a flight path of the sorting objects above the flight path; a lower rectifying plate disposed along the flight path obliquely below the forefront portion of the conveyor under the flight path; and a plurality of injectors (5A, 5B, 5C) that are disposed above the flight path so as to be directed to the flight path, and inject pulse air to the specific material type matter flying from the conveyor, characterized in that wind velocity distribution in a vertical direction of the airflow from a surface of the upper rectifying plate to a surface of the conveyor at the forefront portion of the conveyor has a maximum value in a range of less than 10 mm downward in the vertical direction from the surface of the upper rectifying plate, a ratio obtained by dividing the maximum value by a wind velocity in the vicinity of the surface of the conveyor is 4 or more, and 12 or less, and in a range other than the range of less than 10 mm, the airflow has a wind velocity equal to the wind velocity in the vicinity of the surface of the conveyor. a conveyor that conveys the sorting objects in a placed state in one direction, the sorting objects having the specific material type matter and the other material type matter other than the specific material type matter mixed, and causes the sorting objects to fly at a forefront portion of the conveyor; an identification part that identifies composition of the specific material type matter placed on the conveyor; an air blower (6, 10) that generates an airflow in a flying-out direction of the sorting objects; an upper rectifying plate disposed along a flight path of the sorting objects above the flight path; a lower rectifying plate disposed along the flight path obliquely below the forefront portion of the conveyor under the flight path; and a plurality of injectors (5A, 5B, 5C) that are disposed above the flight path so as to be directed to the flight path, and inject pulse air to the specific material type matter flying from the conveyor, characterized in that wind velocity distribution in a vertical direction of the airflow from a surface of the upper rectifying plate to a surface of the conveyor at the forefront portion of the conveyor has a maximum value in a range of less than 10 mm downward in the vertical direction from the surface of the upper rectifying plate, a ratio obtained by dividing the maximum value by a wind velocity in the vicinity of the surface of the conveyor is 4 or more, and 12 or less, and in a range other than the range of less than 10 mm, the airflow has a wind velocity equal to the wind velocity in the vicinity of the surface of the conveyor.