Abstract: Through the experiment of the high oil breed Dongnong163,the high yield breed Heinong37 and the high protein breed Dongnong42 in every bearing periods sampling. researching dynamic samples analysis of chemical quality yield and quality character of the soybeans. We had the conclusion that the dynamic law of soybean of every character in bearing periods. Through taking the sample to analyse during the different bearing period of the planting soybenan. We had the conclusion that the average weight of the fresh pod and the fresh grain appear the rising tendency at the beginning, but later it appeared to descend. The ration of the grain to pod began to rise . average each grain number was round about 2-3.Through the conclusion that analyse the content of the protein and the oil, we could know that the content the protein which in the high protein strains was the highest during the bearing period , and the content of the oil in the high oil strains was always the highest during every bearing period.