The invention relates to a double-line automatic outer package production line. The production line comprises a small box packaging section A, a small box packaging section B, a middle box packaging section, a large box packaging section and a stacking section. Each small box packaging section comprises a small box opening and labeling all-in-one machine, a product conveyor, a small box empty boxconveyor, a boxing robot, a small box sealing conveyor, a small box transfer conveyor, a small box weighing conveyor, an unpowered buffering storage conveyor and a small box positioning mechanism. Themiddle box packaging section comprises a middle box opening machine, a middle box positioning conveyor, a middle box code scanning conveyor, a middle box sealing conveyor and a middle box positioningmechanism. A large box sealing section comprises a large box opening machine, a double-station positioning and boxing conveyor, a large box sealing conveyor and a large box weighing and stacking positioner. According to the double-line automatic outer package production line, unmanned full-automatic production can be achieved, the packaging efficiency, the packaging quality and the sanitation level are improved, the labor cost is saved, the equipment utilization rate is increased, and the equipment cost and the workshop space area are saved.