To provide a small and portable printer equipped with a convenient magnetic read and write device.

A stepping motor 20 drives a platen 29 in a vertical direction and actuates the spinning of a first and second conveying rollers 21, 22 while actuating the vertical movement of a magnetic head part 31 through the platen 29 and the interlocking mechanism. If the platen 29 moves in the estrangement direction against a printing head 24 of a printing part 23, the contact part 36 of the interlocking mechanism 33 is pushed below, and the whole turns around an interlocking rotary shaft 35 in the clockwise direction, and the lift part 37 of the interlocking mechanism 33 moves upwards, then the magnetic head part 31 is shifted to the direction of a magnetic head pressing member 32 through an energizing member.