To enable to widely change installing conditions of a doctor to maintain a printing quality in response to various printing conditions.

A doctor unit used for gravure print can mount a doctor holder 9 above or below a doctor trestle 1. The holder 9 may be mounted at above or below the trestle 1 in response to printing conditions. The holder 9 can be mounted both above and below the trestle 1, and hence functions of double doctors can be incorporated. A jaw of the holder 9 mounted at the upper side may have an ink return plate 13 having an ink splash preventing function and an ink recovering function.