The present invention relates to an applicator (1) for applying a hair treatment composition. The applicator (1) comprises a plate (10) and a containment portion (20) movably joined by a connection (30) so that said applicator (1) may alternate between a closed state and an open state. A first fin (50), preferably a first (50) and a second (60) fin, projects from the substantially flat internal surface (101) of the plate (10) and bend the hair strand into the containment portion (20) while the applicator (1) is in use. The hair treatment applicator according to the invention allows for precise, non-messy and even application of a hair treatment composition to the hair, in particular to a hair strand and preferably to a bundle of hair strands.
