An easy-open packaging body 1 includes: a container body 10 with a flange 14 formed on a circumference of an opening 13, and a cover 20 heat-sealed to the flange 14 to close the opening 13. Inner and outer notches 15A and 15B enclosing the opening 13 are formed respectively on inner and outer circumferential sides on the flange 14. The flange 14 and the cover 20 are heat-sealed by a first seal part 16A having a predetermined width and formed between the inner and outer notches 15A and 15B to enclose the opening 13 and a second seal part 16B having a width narrower than that of the first seal part 16A and formed within an area of the first seal part 16A to enclose the opening 13 along the first seal part 16A, the second seal part 16B having a projected seal part 17 projected outward relative to the other part on a position corresponding to a tab 21.