A printer includes: a mechanism frame configured to receive a recording medium including a liner having a large length, and a plurality of labels temporarily bonded on the liner; a support member supported on the mechanism frame through intermediation of a support shaft; a head which is mounted to the support member, and is configured to perform printing on at least one of the plurality of labels; and a transmissive sensor which is arranged between the head and the support shaft, and is configured to detect the at least one of the plurality of labels, wherein the mechanism frame includes: a frame portion provided between the head and the support shaft at a distance from the support shaft; and a recessed portion which is formed in the frame portion, and is configured to increase the distance so as to allow the sensor to pass through a space having the distance.