The QLF700A air operated plastic film sack sealing machine, is suitable in the seal length is smaller than 700mm, the weight is smaller than the 50kg plastic bag or the compound bag's intermittent packing seal. This machine uses the compressed air power, the seal pressure adjustable, quality stable reliable, may manual or the foot switch operation, facile simple. In professions and so on chemical industry, grain, food, feed obtains the widespread application.