A sealing ring structure of a cosmetic container comprising: a container main body formed with a hanging step and an assembling recess respectively at an inner round surface and an outer round surface of an upper end opening thereof an inner container having a horizontal flange protruding around an outer round surface thereof to be coupled to the hanging step of the container main body an outer cover formed at an inner round surface thereof with a holding recess; and a inner cover characterized by the fact that the sealing ring structure comprises: a shoulder having at an lower end thereof an inwardly curved ring protruding inwardly to be assembled to the assembling recess in order to finish an upper part of the horizontal flange of the inner container for preventing the inner container from separating; the inner container having at an upper surface thereof a sealing protrusion with a holding step at its outer round surface; the outer cover having at a side thereof a protruding hinge arm to be hinge-coupled to the shoulder; and the inner cover having at an outer round surface thereof a holding protrusion to be coupled to the holding recess of the outer cover, having at an inside of the holding protrusion inner and outer protrusion rings (520, 530) with a predetermined interval therebetween to form a sealing receiving groove, and having at the outer protrusion ring a plurality of elastic holding arms with a predetermined width respectively and with a predetermined interval therebetween to extend downwardly and to have at each lower end a holding protrusion step, the holding protrusion step of the elastic holding arm of the inner cover being elastically held by the holding step of the sealing protrusion of the inner container when the outer cover is closed by its hinge-rotation, and an upper end of the sealing protrusion tightly contacting the sealing receiving groove when it is inserted in the sealing receiving groove at the same time so that a receiving room of the inner container is sealed. a container main body formed with a hanging step and an assembling recess respectively at an inner round surface and an outer round surface of an upper end opening thereof an inner container having a horizontal flange protruding around an outer round surface thereof to be coupled to the hanging step of the container main body an outer cover formed at an inner round surface thereof with a holding recess; a shoulder having at an lower end thereof an inwardly curved ring protruding inwardly to be assembled to the assembling recess in order to finish an upper part of the horizontal flange of the inner container for preventing the inner container from separating; the inner container having at an upper surface thereof a sealing protrusion with a holding step at its outer round surface; the outer cover having at a side thereof a protruding hinge arm to be hinge-coupled to the shoulder; and the inner cover having at an outer round surface thereof a holding protrusion to be coupled to the holding recess of the outer cover, having at an inside of the holding protrusion inner and outer protrusion rings (520, 530) with a predetermined interval therebetween to form a sealing receiving groove, and having at the outer protrusion ring a plurality of elastic holding arms with a predetermined width respectively and with a predetermined interval therebetween to extend downwardly and to have at each lower end a holding protrusion step, the holding protrusion step of the elastic holding arm of the inner cover being elastically held by the holding step of the sealing protrusion of the inner container when the outer cover is closed by its hinge-rotation, and an upper end of the sealing protrusion tightly contacting the sealing receiving groove when it is inserted in the sealing receiving groove at the same time so that a receiving room of the inner container is sealed.