We developed a suitable transplanter (electric semi-automatic type) for a spinach transplanting cultivation system using plug seedlings. This transplanter is light-weight (about 50kg) and optimizes to four rows with 15cm spacing between rows by two operators. Transplant efficiency was equal to or twice that of the hand planting. Labor stress on the bones and muscle system during transplanting using the transplanter showed marked improvement on evaluation by OWAS (Ovako Working Posture Analyzing System). The inclination of the worker's body when transplanting with the transplanter differed depending on the stature of the worker. The influence on the heart rate increase using the transplanter differed depending on worker's physical characteristics.