Abstract: The cosmetic brush case includes an upper cover, a lower cover, and a plurality of brush holders. The upper cover, lower cover and holders are connected by a hinge pin so that they can rotate about the pin. Each holder retains each of brushes. One of two adjacent holders has a protrusion extending toward the other of the holders. The other of the holders has an arc-shape groove for receiving the protrusion. The protrusion can move along the groove when the one of the two holders rotates. After the protrusion reaches an end of groove two adjacent holders rotates together. By the above constitution, the holders can be spread out in a fan shape when the case is opened.