The utility model has the advantages of good air tightness, excellent moisture retention and sealing performance; The degree of isolation is high, and the degree of oxygen and moisture permeability is extremely low; Strong ability to prevent damp and mildew; The appearance is bright and beautiful, non-toxic and tasteless; After bagging, it can be unfolded into a three-dimensional bag, with high space utilization rate; In addition to the points mentioned above, the three side sealing bag has strong expansibility and can be customized as required. The resealable zipper, easy tear opening and hanging hole for shelf display can be realized on the three side sealing bag.