PURPOSE: To obtain dot printer having two kinds of functions, that is, a dot impact printer and a current supply thermal transfer printer, by changing over a switch.

CONSTITUTION: When a switch 1 is connected to C1 to select a dot impact printer, a current is selectively supplied to an electromagnet 3 from a drive power source 6 and the electromagnet 3 attracts an armature 7 to allow the wire 4 mounted on the armature 7 to collide with paper 9 in such a state that the ribbon 8 for the impact printer is interposed between the wire and the paper. When the switch 1 is connected to C2, the armature 7 is always contacted with a stopper 11 by a spring 13 and the leading end of the wire 4 is flushed with a wire guide 14. At this time, a printing head 2 presses a current supply heat transfer ribbon 10 and paper 9 to a platen 12 and a current is selectively supplied to the wire 4 from the drive power source 6 and further supplied to the ribbon 10 connected to the wire 4.