A cosmetic container having an airtight structure comprising: a rotary cover forming the upper surface of the cosmetic container; a lower body forming the lower surface of the cosmetic container; and a cosmetic substance housing member, characterized in that the rotary cover has an elastic member provided on the lower surface thereof and a plurality of stoppers and guide grooves provided radially along the inner circumference thereof; and that the cosmetic container further comprises: a mirror cover having a first hinge provided at one side thereof and a plurality of side protrusions provided along the outer circumference thereof in such a manner as to be inserted rotatably to left and right sides into the plurality of guide grooves of the rotary cover at a state of closely contacting with the elastic member of the rotary cover; a middle body adapted to be inserted into the inner surface of a lower body and having a plurality of anti-loosing means provided inclinedly on the outer periphery thereof such that the plurality of stoppers of the rotary cover are adapted to be rotatably coupled with the plurality of anti-loosing means; the lower body being coupled with the first hinge of the mirror cover in such a manner as to be rotatable upward and downward; the cosmetic substance housing member being adapted to be inserted at the inside of the middle body for housing cosmetic substance therein; and a cosmetic implement container mounted along the upper periphery of the middle body and having a second hinge provided at one side thereof for coupling with the middle body in such a manner as to be rotatable upward and downward and a packing member provided along the lower periphery thereof; wherein if the plurality of stoppers of the rotary cover are pushed downward along the inclined faces of the plurality of anti-loosing means of the middle body coupled along the lower periphery of the rotary cover, the lower periphery of the mirror cover is compressed against the upper periphery of the cosmetic implement container mounted on the upper periphery of the middle body by the elastic force of the elastic member of the rotary cover, thereby preventing air from flowing to the inside of the cosmetic container. a mirror cover having a first hinge provided at one side thereof and a plurality of side protrusions provided along the outer circumference thereof in such a manner as to be inserted rotatably to left and right sides into the plurality of guide grooves of the rotary cover at a state of closely contacting with the elastic member of the rotary cover; a middle body adapted to be inserted into the inner surface of a lower body and having a plurality of anti-loosing means provided inclinedly on the outer periphery thereof such that the plurality of stoppers of the rotary cover are adapted to be rotatably coupled with the plurality of anti-loosing means; the lower body being coupled with the first hinge of the mirror cover in such a manner as to be rotatable upward and downward; the cosmetic substance housing member being adapted to be inserted at the inside of the middle body for housing cosmetic substance therein; and a cosmetic implement container mounted along the upper periphery of the middle body and having a second hinge provided at one side thereof for coupling with the middle body in such a manner as to be rotatable upward and downward and a packing member provided along the lower periphery thereof; wherein if the plurality of stoppers of the rotary cover are pushed downward along the inclined faces of the plurality of anti-loosing means of the middle body coupled along the lower periphery of the rotary cover, the lower periphery of the mirror cover is compressed against the upper periphery of the cosmetic implement container mounted on the upper periphery of the middle body by the elastic force of the elastic member of the rotary cover, thereby preventing air from flowing to the inside of the cosmetic container.