The utility model provides a horizontal airflow sorting machine which comprises a sorting bin and an air supply system, at least two air inlets are longitudinally formed in one side wall of the sorting bin, an air outlet is formed in the other side wall of the sorting bin, and the air outlet is opposite to the highest air inlet in the at least two air inlets; a vertically-arranged partition plateis arranged in the sorting bin and divides the sorting bin into at least two independent air channels, the independent air channels are communicated with the air inlets, and all the independent air channels are communicated with the air outlet. A heavy material leading-out channel used for leading out heavy materials and a light material leading-out channel used for leading out light materials aresequentially arranged at the bottom of the sorting bin in the direction from the air inlet to the air outlet; and the feeding hopper is arranged at the top of the sorting bin close to the at least two air inlet sides. Due to the fact that the partition plates are additionally arranged in the sorting bin, the interior of the sorting bin can be conveniently divided into at least two independent airducts, wind power fields are independent of each other, and mutual influence caused by falling of materials is avoided.