Plowless cultivation of soy bean was carried out using a hill seeding machine at the same time of harvest of wheat. It was found that this plowless culture of soy bean was a more effective labor-saving culture method than usual culture method such as the plowing-incorporation of wheat straw into soil before the sowing of soy bean. Further, the new culture method effectively prevents the bird injuries and raised the germination percentage of soy bean. However, since the plowless culture method resulted in a slightly lower yield of soy bean than the usual method, it should be improved on the population of soy bean. Topdressing with nitrogen at the beginning of the thickening growth of soy bean was considerably effective in an increase of soy bean yield.