PROBLEM TO BE SOLVED: To improve a seedling planting accuracy.SOLUTION: The seedling transplanter includes: a travel device; a seedling conveyance part conveying a seedling; and a seedling planting device 6 planting the seedling conveyed by the seedling conveyance part to a planting feed position on a farm field. The seedling planting device 6 plants the seedling on the farm field by operating a seedling planting holder 31 holding the seedling at the planting feed position in a trajectory long in a fore-and-aft direction. A transmission switching mechanism 87 is arranged which is switchable to a constant velocity transmission state for transmission to a transmission passage to the seedling planting device 6 at a constant velocity and a non-constant velocity transmission state for transmission at a non-constant velocity. An insertion length of the seedling into soil by the seedling planting device 6 is longer in the non-constant velocity transmission state than the constant velocity transmission state.SELECTED
