Abstract: A posture holding mat according to the present invention is a mat which has a predetermined thickness to hold a posture, the posture holding mat includes: an elastic foam; and a cuttable line which allows the mat to be cut to a predetermined size and in the cuttable line, cuts penetrating in the direction of the thickness are provided at a predetermined interval. In this way, the posture holding mat can be cut by an operator with fingers without use of a cutting tool such as a cutter, can be bent to be used and can be used for holding the posture of a subject during an operation in orthopedics, surgery or the like.