To reduce the number of parts of a bristle holder and to prevent bristles from being accidentally retracted into an outer barrel while using a conventional cosmetic brush including a grooved outer barrel with a hook groove formed in the axial direction, the bristle holder retractably inserted into the outer barrel, holding bristle tufts at one end and having a hard resin plug fixed at the other end, and a headed pin screwed and fixed to the plug via a hook groove of the outer barrel.

The bristle holder 11 is a single body made of hard resin, and a pair of slits 16 are formed with a fixed space between them in the circumferential direction on one side. A free end of an inter-slit part 14c is resiliently brought into contact with the outer barrel while a base projecting from the inter-slit part 14c is engaged with a locking hole of the hook groove formed in the outer barrel.