The invention discloses an automatic material distributing machine. The automatic material distributing machine comprises a supporting device, a conveying device and a motor; the supporting device comprises a base and a supporting column; the lower end of the supporting column is fixed to the base, and the top end of the supporting column is rotationally connected with the bottom of the conveying device; the conveying device comprises a conveying table and a conveying belt which is arranged on the conveying table; a double-helix lead screw is arranged on the lower side of the rear end of the conveying table; the motor controls the conveying belt to convey materials; meanwhile the motor controls the conveying table to swing leftwards and rightwards along the spiral lead screw; and the arrangement of the double-helix lead screw guarantees the stability, constant-speed performance and reliability during left and right reciprocating swing of the conveying device, and therefore the materials can uniformly fall on a feeding table, manual flattening is not needed, and the work efficiency is improved.