The invention discloses a cloth middle conveying device with an automatic dust collection mechanism. The cloth middle conveying device comprises a rack, wherein vertical supporting plates are fixed at two sides of a top plate of the rack; two ends of a lower transmission roller are hinged to lower parts of the two vertical supporting plates; a driving motor is fixed on one vertical supporting plate; an output shaft of the driving motor is a spline shaft; the spine shaft is inserted into a spline hole formed in one end of the lower transmission roller; an upper transmission roller is located just above the lower transmission roller; two ends of the upper transmission roller are hinged to movable blocks; the movable blocks are inserted into movable through grooves formed in the upper parts of the vertical supporting plates; adjusting bolts are in screw joint with top surfaces of the vertical supporting plates; and bottom ends of the adjusting bolts stretch into the movable through grooves and are hinged to the top surfaces of the movable blocks. According to the cloth middle conveying device provided by the invention, automatic dust collection in a cloth conveying process can be realized; and meanwhile, a main air suction head is convenient to mount and detach, and is convenient to replace and maintain.