The disclosure provides an applicator for applying a cosmetic treatment product to the skin or the lips, the applicator comprising at least:an application portion comprising a bundle of needles for applying the cosmetic treatment product and extending along a longitudinal axis, the bundle of needles comprising at least one first set of needles having a distribution that is square in cross-section relative to the longitudinal axis； anda linear drive device connected to the application portion and configured to constrain the bundle of needles to perform reciprocating motion along the longitudinal axis.
