A small automatic production line for covering bottoms of packaging boxes comprises a mold conveying line, molds and a feeding table, wherein the molds are arranged on the mold conveying line, the molds can be circularly moved through the mold conveying line, accurate positioning of the molds can be achieved by using the mold conveying line and a positioning and deviation correcting device, and feeding, bonding, discharging and other operations are carried out on multiple stations at the same time. The feeding table is internally provided with the feeding station, the gluing station and the discharging station, and all process steps are completed circularly through an annular workbench. Feedback signals are generated by using a proximity sensor, and a driving motor is controlled to be started and stopped to complete accurate positioning of the molds and a feeding and discharging mechanism. Meanwhile, due to the design of a mechanical deviation correcting mechanism, the position deviation existing on the production line can be reduced to the maximum degree, and the production precision of the packaging boxes is guaranteed. The production efficiency can be greatly improved through the circulation type production line and the annular structure of the feeding table, and the occupied area and investment cost of equipment are reduced.