Abstract: The invention of automatic online defective elements checking and removing device relates to flexographic printing presses. Between a first vacuum conveying platform and a second vacuum and separating-conveying platform on the top of a mobile frame is provided a defective elements remover including a defective removing air ejector operated by a valve, which receives output signal from the online computerized visual QC station at the flexographic printing press and a receiver for carrying the ejected elements away from the platforms. Under the mobile frame is provided a vacuum pump and vacuum distribution tube connected each other with steel wire enforced hose and a ball valve is used to adjust the vacuum in order to prevent the printed labels from drifting on the conveyor belts. Both of the platforms are separately driven by motors and via toothed belts.