An object of the present invention is to provide a mascara applicator capable of being fitted to the curved bases of eyelashes to lift up eyelashes, providing voluminousness to the eyelashes by adhering a mascara to the bases of the eyelashes, widely applying the mascara so that the eyelashes expand in the form of a fan, properly and widely applying the mascara to detailed parts such as the tail and inner corner of the eye, as well as lower eyelashes, and also obtaining an all direction expansion mascara application result. A mascara applicator (1), which has a long core member (2), and an application part configured by an upper application part (5) and a lower application part (6) that are supported by the core member (2), extend from the core member to the outside in a horizontal sectional direction, carry a mascara thereon, and apply the mascara to eyelashes, the lower application part being set to be shorter than the upper application part in the horizontal section, wherein a cross section of the upper application part along a longitudinal direction of an axis of the core member is shaped into a series of crests with one and half crests along the longitudinal direction between a base end part and tip part of the core member.