Method for decorating at least one surface to be decorated of a mechanical part comprising the following steps of: - taking the mechanical part to be decorated, on which at least one decoration element (2a, 2b) is sought to be produced according to a predetermined thickness and contour; - depositing, on the at least one surface to be decorated of the mechanical part, a first bonding layer; - depositing, on the at least one surface to be decorated of the mechanical part, a masking layer having a thickness that is at least equal to the thickness of the at least one decoration element (2a, 2b) to be produced and the bonding of which is facilitated by the first bonding layer; - making, in the masking layer, at least one first cavity (14a, 14b) that coincides with the location on the at least one surface to be decorated of the mechanical part where the at least one decoration element (2a, 2b) is to be produced, the at least one first cavity (14a, 14b) having a contour that corresponds to the contour of the at least one decoration element (2a, 2b) to be produced and defining a volume with the at least one surface to be decorated of the mechanical part; said method being characterised in that it comprises the succession of the following steps: - depositing, on the at least one surface to be decorated of the mechanical part, in the location where the at least one first cavity (14a, 14b) is made, a second bonding layer to facilitate the bonding of the at least one decoration element (2a, 2b); - filling the volume delimited by the at least one first cavity (14a, 14b) with a filling material in which the at least one decoration element (2a, 2b) is intended to be produced; - removing the masking layer. - taking the mechanical part to be decorated, on which at least one decoration element (2a, 2b) is sought to be produced according to a predetermined thickness and contour; - depositing, on the at least one surface to be decorated of the mechanical part, a first bonding layer; - depositing, on the at least one surface to be decorated of the mechanical part, a masking layer having a thickness that is at least equal to the thickness of the at least one decoration element (2a, 2b) to be produced and the bonding of which is facilitated by the first bonding layer; - making, in the masking layer, at least one first cavity (14a, 14b) that coincides with the location on the at least one surface to be decorated of the mechanical part where the at least one decoration element (2a, 2b) is to be produced, the at least one first cavity (14a, 14b) having a contour that corresponds to the contour of the at least one decoration element (2a, 2b) to be produced and defining a volume with the at least one surface to be decorated of the mechanical part; said method being characterised in that it comprises the succession of the following steps: - depositing, on the at least one surface to be decorated of the mechanical part, in the location where the at least one first cavity (14a, 14b) is made, a second bonding layer to facilitate the bonding of the at least one decoration element (2a, 2b); - depositing, on the at least one surface to be decorated of the mechanical part, in the location where the at least one first cavity (14a, 14b) is made, a second bonding layer to facilitate the bonding of the at least one decoration element (2a, 2b); - filling the volume delimited by the at least one first cavity (14a, 14b) with a filling material in which the at least one decoration element (2a, 2b) is intended to be produced; - removing the masking layer.