The utility model relates to a structure of a packaging bag, which comprises a bag body with an internal containing space. An opening of the bag body is provided with two sealing trim strips at interval; the sealing trim strips consist of ledges and grooves, which are embedded correspondingly, and respectively and fixedly arranged at the inner surface of the opening of the bag body, and penetrate through two ends of the bag body horizontally. Due to the structure, the packaging bag has double-layer sealing protective performance, and has better sealing property.