A portable printer includes a casing configured to receive a recording medium; a head configured to perform printing on the recording medium; a platen roller, which is arranged so as to be opposed to the head, and is configured to convey the recording medium while sandwiching the recording medium together with the head; a button, which is provided on the casing, and is configured to perform operation of separating the head and the platen roller from each other; and a stepped portion, which is formed on the casing along a peripheral edge of the button, and protrudes so that an inner side of the casing is higher than an outer side of the casing.