Abstract: This paper studies on the energy metabolism in the process of photo-synthesis, respiration and transpiration of the soybean (Glycing soja) seedling stage. The results show that the energy input is 990 kcal·m^-2. h^-1, the energy absorbing is 40.42 kcal·m^-2. h^-1, the energy fixing is 14.71kcal·m^-2.h^-1, the energy dissipating is 28.61 kcal·m^-2. h^-1 and theenergy accumulating is 11.71 kcal·m^-2.h^-1, in the process of the energymetabolism of soybean (Glycing soja) seedling stage. That can be seen thatmost of the energy is lost in the energy metabolism, of which the tra-nspiration of the soybean dissipates 25.71 kcal·m^-2.h^-1 and the photo-respiration and respiration of the soybean dissipates only 3. 00 kcal·m^-2.h^-1. Thus, the efficiency of the energy utilization is 1.18% in its seedlingstage.

Key words: soybean, seedling stage, the energy metabolism