This research is to develop a transplanting mechanism for the flower-plug- seedling. The mechanism can transplant seedlings from high density plug trays into low density growing flats. A programmable logic controller is used to control the transplanter which is driven by pneumatic devices. To adjust the velocity and to reduce the error of position-settling of rodless cylinder, the 2-position-2-way valves are used. The transplanting rate is about 40 seedlings per minute.