An upper structure of a female snap button, comprising: a post holding member for holding a post of a male snap button, the post holding member comprising a tube that extends in an up and down direction; and a receiving member for receiving the post holding member, the receiving member comprising: a surrounding wall that extends in the up and down direction to surround the post holding member; a bottom portion that is coupled to a lower end of the surrounding wall and provided inward of the surrounding wall; and a peripheral portion that is coupled to an upper end of the surrounding wall and provided outward of the surrounding wall, wherein the post holding member is insertable into a space defined by the surrounding wall of the receiving member via an opening defined by a rim between the upper end of the surrounding wall and the peripheral portion, characterized in that the post holding member is an elastic member and further comprises: one or more locking portions for locking the post, said one or more locking portions being projected from an inner circumferential surface of the tube and being provided at an upper end of the tube; and one or more contact portions for touching an inner circumferential surface of the surrounding wall, said one or more contact portions being projected from an outer circumferential surface of the tube and being provided at a lower end of the tube. a post holding member for holding a post of a male snap button, the post holding member comprising a tube that extends in an up and down direction; and a receiving member for receiving the post holding member, the receiving member comprising: a surrounding wall that extends in the up and down direction to surround the post holding member; a bottom portion that is coupled to a lower end of the surrounding wall and provided inward of the surrounding wall; and a peripheral portion that is coupled to an upper end of the surrounding wall and provided outward of the surrounding wall, wherein the post holding member is insertable into a space defined by the surrounding wall of the receiving member via an opening defined by a rim between the upper end of the surrounding wall and the peripheral portion, characterized in that the post holding member is an elastic member and further comprises: one or more locking portions for locking the post, said one or more locking portions being projected from an inner circumferential surface of the tube and being provided at an upper end of the tube; and one or more contact portions for touching an inner circumferential surface of the surrounding wall, said one or more contact portions being projected from an outer circumferential surface of the tube and being provided at a lower end of the tube. a surrounding wall that extends in the up and down direction to surround the post holding member; a bottom portion that is coupled to a lower end of the surrounding wall and provided inward of the surrounding wall; and a peripheral portion that is coupled to an upper end of the surrounding wall and provided outward of the surrounding wall, wherein the post holding member is insertable into a space defined by the surrounding wall of the receiving member via an opening defined by a rim between the upper end of the surrounding wall and the peripheral portion, characterized in that the post holding member is an elastic member and further comprises: one or more locking portions for locking the post, said one or more locking portions being projected from an inner circumferential surface of the tube and being provided at an upper end of the tube; and one or more contact portions for touching an inner circumferential surface of the surrounding wall, said one or more contact portions being projected from an outer circumferential surface of the tube and being provided at a lower end of the tube. one or more locking portions for locking the post, said one or more locking portions being projected from an inner circumferential surface of the tube and being provided at an upper end of the tube; and one or more contact portions for touching an inner circumferential surface of the surrounding wall, said one or more contact portions being projected from an outer circumferential surface of the tube and being provided at a lower end of the tube.