The invention relates to an automatic continuous production line for plastic packaging bags. The automatic continuous production line comprises an automatic feeding device, an automatic film forming device, an automatic printing device, an automatic flattening device, an automatic folding device, an automatic pattern printing device and an automatic winding device which are sequentially arranged and connected with a programmable logic controller (PLC) for centralized control, the PLC is further connected with a motor, a solenoid valve, a heating element, a frequency converter and an industrial computer. After adoption of the structure, a plurality of manual machining progresses for producing the plastic packaging bags are finished by one production line, mechanical devices are effectively controlled by modern technological means such as the computer, the frequency converter and the solenoid valve, rhythms of all portions of the production line are uniform and coordinate with one another, the machining efficiency is substantially improved, the machining cost is reduced, working places can be saved due to usage of the production line, the labor intensity of workers can be reduced effectively, and the product quality can be improved.