To provide a plate snapping-off apparatus having no wasteful operation to move a squeegee and a screen printer having a fast printing speed and a high printing efficiency.

In this printer, a plate 1 is fixed to a plate fixing unit 10. The unit 10 is supported by a bearing unit 5 of a bearing via an oscillating shaft 6 to become an oscillating fulcrum. The shaft 6 is set to become a center of a printing surface. An oscillating force generator has a cam 7, a cam follower 8 and a restricting spring 9. Further, the snapping-off apparatus conducting an operation for inclining the plate by rotating the cam 7 is provided.