To correct a posture of a paper sheet inserted from various positions and angles to a normal transport state without causing any deformation due to contact with a side wall while transporting the paper sheet continuously and non-intermittently. A drive-side unit (20) includes at least one drive roller (25) that is supported rotatably about a shaft orthogonal to a normal paper-sheet transport direction and axially movably, an elastic biasing member (40) that elastically biases the drive roller in an axial direction, and a cam mechanism (50) that transmits a driving force from a driving source to the drive roller, and operates when an external force exceeding a predetermined value in a direction other than a normal transport direction is applied to the paper sheet transported by the drive roller, so as to change an axial position of the drive roller against an elastic biasing force, and a driven-side unit (100) includes a driven roller that changes a transport grip between the drive roller and a paper sheet according to a change of an axial position of the drive roller.