A clothes treatment apparatus comprising: a cabinet having a treatment chamber for allowing clothes to be hung therein and a cycle chamber for allowing machinery to be installed therein; a blowing unit installed in the cycle chamber for circulating air in the treatment chamber; and a scent diffuser separably disposed in the treatment chamber for diffusing scent into the treatment chamber, wherein the scent diffuser comprises: a holder, in which a replaceable scent member is mounted, the holder having at least one discharge port, through which scent emitted from the scent member is discharged; and a slider having a manipulation part exposed outward from the holder, the slider being movable relative to the holder when force generated by manipulation of the manipulation part is transmitted to the slider, the slider being configured to adjust an extent of opening of the discharge port based on a position to which the slider has been moved, characterised in that the holder comprises a first holder member and a second holder member, the first holder member and the second holder member being rotatable relative to each other, a scent member installation space, in which the scent member is mounted, and a slider installation space, in which the slider is mounted, are formed between the first holder member and the second holder member, the first holder member comprises: a plurality of discharge ports formed so as to constitute a line; and a slit connected to one of the discharge ports for guiding movement of the slider, and the slider comprises: a plate disposed in the slider installation space such that the plate moves along the holder so as to cover the discharge ports; an opening adjustment port formed in the plate, the opening adjustment port being configured to overlap the discharge port so as to expose the scent member outward; and the manipulation part inserted through the discharge port connected to the slit such that the manipulation part is exposed outward from the first holder member, the manipulation part being moved along the slit according to a user's manipulation of the manipulation part. a cabinet having a treatment chamber for allowing clothes to be hung therein and a cycle chamber for allowing machinery to be installed therein; a blowing unit installed in the cycle chamber for circulating air in the treatment chamber; and a scent diffuser separably disposed in the treatment chamber for diffusing scent into the treatment chamber, a holder, in which a replaceable scent member is mounted, the holder having at least one discharge port, through which scent emitted from the scent member is discharged; and a slider having a manipulation part exposed outward from the holder, the slider being movable relative to the holder when force generated by manipulation of the manipulation part is transmitted to the slider, the slider being configured to adjust an extent of opening of the discharge port based on a position to which the slider has been moved, characterised in that the holder comprises a first holder member and a second holder member, the first holder member and the second holder member being rotatable relative to each other, a scent member installation space, in which the scent member is mounted, and a slider installation space, in which the slider is mounted, are formed between the first holder member and the second holder member, the first holder member comprises: a plurality of discharge ports formed so as to constitute a line; and a slit connected to one of the discharge ports for guiding movement of the slider, and the slider comprises: a plate disposed in the slider installation space such that the plate moves along the holder so as to cover the discharge ports; an opening adjustment port formed in the plate, the opening adjustment port being configured to overlap the discharge port so as to expose the scent member outward; and the manipulation part inserted through the discharge port connected to the slit such that the manipulation part is exposed outward from the first holder member, the manipulation part being moved along the slit according to a user's manipulation of the manipulation part.