To provide a plastic bag aimed at environmental pollution prevention, preventing the causing of environmental pollution from the use of a large or small bag, or a large number of bags when using the grocery bag.

A frame 4 is formed by use of flat rubbers 1, 2, 3, cloths 5, 5' are stretched between both ends of the flat rubbers 1, 2, 3 to form a bag 6, the flat rubbers 1, 2, 3 and the cloths 5, 5' are sewn by a rubber thread 7, projecting snaps 8, 9, 10, 11 are provided in a central part of the front surface of the cloth 5, and recessed snaps 8', 9', 10', 11' are provided in a central part of the rear surface of the cloth 5'.