The invention discloses an automatic balancing device for discharging outlet material receiving plates of a parallel-connection mining crusher, and belongs to the field of coal mine mechanical equipment. The automatic balancing device comprises the material receiving plates (1), a rotary bottom plate device (3), a single-chip microcomputer (5) and a supporting seat (8). A hydraulic control device (2) is connected between each material receiving plate and the rotary bottom plate device (3); the rotary bottom plate device (3) is hinged to the supporting seat (8); an inclination angle sensor (4) is arranged on a bottom plate (3-1); each hydraulic cylinder (2-2) is provided with a magnetostrictive displacement sensor (6); the output ends of the inclination angle sensor (4) and the magnetostrictive displacement sensors (6) are connected with the input end of the single-chip microcomputer (5), and the output end of the single-chip microcomputer (5) is connected with control circuits of the hydraulic control devices (2). The automatic balancing device can automatically adjust the balance of the two material receiving plates to reasonably distribute the positions of materials which fall onto a conveying belt, so that the abrasion damage to the conveying belt is relieved. The automatic balancing device for the discharging outlet material receiving plates of the parallel-connection mining crusher is good in adaptability, good in anti-disturbance performance and long in service life.