The invention provides a box opening system and an automatic cigarette sorting system. The box opening system comprises a laser cutting mechanism, a sealing cover opening mechanism, a smoke pushing mechanism and a smoke box recycling mechanism, wherein sealing glue on sealing covers on the two sides of a smoke box is ripped by the laser cutting mechanism according to the preset shape; after the sealing glue of the smoke box is ripped, the sealing covers on the two sides of the smoke box are opened by the sealing cover opening mechanism; carton cigarette stacks in the smoke box are conveyed into a smoke temporary storing mechanism from the interior of the smoke box by the smoke pushing mechanism; and the smoke box recycling mechanism is used for recycling the smoke box. According to the method, the sealing glue of the sealing covers on the two sides of the smoke box is ripped through the laser cutting mechanism, after that, the sealing covers are opened through the sealing cover openingmechanism, after the sealing covers are opened, the carton cigarette stacks are conveyed into the smoke temporary storing mechanism by the smoke pushing mechanism, finally the smoke box recycling mechanism is used for recycling the smoke box, automatic box opening and recycling of cigarette are achieved, and the sorting efficiency is improved.