It is well known that the supply of fertilisers and manures to the soils is considered by the farmers to be most important in agricultural practice. The writers were much interested in researching the factors which affect,he plant growth. Among them the available plant nutrients attracted their attention. The work done fell in two parts in convenience. The first. part of work was stressed to the observations of plant growth and soil analyses in order to secure general conception about the correlation between the degree of plant growth and available plant nutrients found in soils. Crops for studying were rice, wheat, rape seed, and corn. Each of them growing in the field in the best condition in comparision with the worst was selected to he observed carefully. All the characteristics of crops, including the color, broadth, and length of leaves, alegree of lodgging of stalk, root systems, and the abnormal sign found, were recorded. The soils surrounding the root systems of crops were collected at surface and surface layers. The items of chemical analyses of soil samples consisted of pH value, humus content, water soluble plant nutrients, which are considered to play an important part in chemical property of soil, in relation to crop growth.