The present invention relates to a tissue protection device for mitral valve cerclage annuloplasty and, more particularly to a tissue protection device for protecting tissues of the body (heart) during mitral valve cerclage annuloplasty that is performed on a mitral valve cerclage patient with mitral regurgitation. The tissue protection device for mitral valve cerclage annuloplasty of the present invention is a hollow cylindrical tube where cerclage sutures (10a, 10b) are inserted, in which a hole (22) is formed at a predetermined portion of the cylindrical tube so that a coronary sinus cerclage suture (10a) inserted in a coronary sinus comes out of the cylindrical tube, and a lower section from the hole is inserted into the tricuspid valve to protect tissues of the tricuspid valve and the ventricular septum.