Abstract: The developing characteristics of individual plant and the correlation of these characteristics with grain yield were studied for summer foxtail millet(Setaria Italic L.Beauv.)of high and dwarf plant types.The results showed that the difference between high and dwarf plants existed in individual growing progress and grain yield formation.The development of dwarf plant at prophase was earlier than that of high plant.The nutrient accumulation and translation during the period of head milking in high plant were significant,but those of the dwarf plant were not.The grain yield formation of dwarf plant was mainly from the outcome of photosynthesis after flower,but that of the high plant was from the nutrient transferred from plant and the outcome of photosynthesis after flower.According the growth feature and developing characteristics of millet,the dwarf plant should be planted in narrow row and high density;the high plant should be planted in wide row and suitable density.Promoting early stage development and keeping long lived organ at later stage should be adopted in dwarf plant.The high plant should avoid more nutrient accumulating at maturing stage and avoid latematuring.By this way,high yield can be expected.