To provide a groove-cutting machine capable of performing a groove-cutting work in a good efficiency in a technical field associated with a groove-cutting machine for forming by push-cutting a relatively shallow and narrow width groove on a rice paddy, farmland, or the like.

This groove-cutting machine is obtained by mounting a disc-formed groove-cutting body 2 whose circumferential edge is formed to have a chevron-formed cross section, and rotatably on the rear part of a traveling machine body 1. The groove-cutting body 2 is made as capable of turning relatively to the progressing direction of the traveling machine body 1. On turning at the end of a paddy, or the like, since the groove-cutting body follows the traveling machine body by turning in soil, it is not necessary to pull up the groove-cutting body from the surface of the paddy, or the like, and therefore it is possible to perform the groove-cutting work in a good efficiency.