PROBLEM TO BE SOLVED: To provide a mattress that improves stability for a seated position at an end and stability for rising by additionally eliminating a hardness gap, which is a hardness difference between a mattress peripheral edge part and a flexible mattress central part, while imparting rigidity to the mattress peripheral edge part, and that also has an improved structure for making it easy for a user to turn over on the mattress.SOLUTION: A mattress includes a mattress unit having: a central block disposed in a central part of the mattress in a width direction thereof and supporting at least the back and waist of a user in a supine posture and end blocks arranged at both ends of the mattress in the width direction and supporting at least shoulder parts of the user in a supine posture. The central block is formed so as to be more flexible than an outer peripheral edge part of each end block. The end block is provided with hardness adjustment means that makes an adjustment so as to form a hardness inclination in which the apparent hardness of the end block gradually decreases in a direction in contact with the center block and the apparent hardness in a part in contact with a shoulder part of the user in a supine posture is lower than the apparent hardness of the central block.SELECTED DRAWING: Figure 1