Cosmetic case having sealing function

Provided is a cosmetic case having a sealing function which prevents a gap from being formed between a main body and a cover, thus preventing cosmetics from being contaminated during a process of distribution. In the cosmetic case, a suction member can be reliably attached to the main body by suction force so that a gap is prevented from being formed therebetween. Therefore, cosmetics contained in the main body can be prevented from being contaminated during a process of distribution, and the weight of cosmetics can be maintained. Furthermore, when the user presses a button member, a cover opens and, simultaneously, the suction force of the suction member is removed, thus allowing the user to easily open the cover and suction cover unit.