A cassette (2) for feeding sheet materials (214a, 214b) is equipped with a container body (4) in which two sheet material-holding means (36a, 36b) are arranged in parallel in the direction of width. Each of the sheet material-holding means includes a pair of width restriction members (38a, 38b, 40a, 40b) constituted by width restriction members of the one side (38a, 38b) and the other side (40a,40b) which are so disposed that their positions can be freely adjusted in the direction of width. Each of the sheet material-holding means further includes a rear end restriction member (134a, 134b) that is so disposed that its position can be freely adjusted in the feeding direction.