PROBLEM TO BE SOLVED: To provide a seedling-planting apparatus for suppressing a state, in which a load to be borne on a drive shaft is varied in accordance with the rotation phase of the drive shaft of a rotary case.SOLUTION: A seedling-planting apparatus comprises animal power storing mechanisms 36, 37 and 38 for performances of power storage and release on the basis of the rotation of a rotary case 6. In the earlier half from a takeout position E2 to a planting position E1, the forces of the force storing mechanisms 36, 37 and 38 for storing and releasing an animal power on the basis of the rotations are released to rotate a planting arm 7 in a direction to assist the state, a seedling extrusion tool 26. In the later half from the planting position E2 to the takeout position E1, the force is stored in the force storing mechanisms 36 to 38. Before the takeout position E1, the forces of the force storing mechanisms 36 to 38 are released so that the planting arm 7 may turn to the upstream side of a rotation direction of the rotary case 6 by the extent of the backlash of a planting gear 20 of the planting arm 7.
