1. The development of the cooperative group farm playedanimportant role in the growth of the Japanese poultry industry and has a large influence in other agricultural sectors.<br>2. The Yoro and Ukino poultry cooperative group farms selected and considered in this study are typical cases.<br>3. The typical farming system in Japan had long been the system to produce rice and wheat with draft animals. But with agricultural mechanization, poultry raising: has expanded in order to obtain poultry manure which was once obtained as manure of the draft animal and to enable additional income to that from rice and wheat. Rural cooperatives have had an important role in introducing poultry business to their farms such as pullet growing business, culled hen processing and egg marketing, and technical backup was also given by the cooperative. In other words, the egg production expanded largely because of using the same type or variety of poultry breed, mixed feed, cages and management pattern, and there was increased production of rice and wheat due to the application of poultry manure.<br>However, since poultry farms had only small flocks and were too dispersed in the districts, it took too much time and transportation cost to carry the mixed feed, pullets and eggs produced. Moreover, the system had no effective measures against poultry disease and its expansion was restricted by the limited area of farm backyards in the clustered village. The Yoro and Ukino poultry cooperative are typical examples of the first stage of a poultry group farm.<br>4. The second stage of poultry group farm may be characterized as follows: Poultry farms are consolidated on the corner of the village field and just outside of the clustered village. It is a large poultry joint farm enterprise handling feed mixing, pullet growing, manure drying plant, chicken and egg processing plant and office.<br>This system to group farms for egg production not only has a greater number of layers, but lowers transportation costs for the mixed feed, chickens, pullets and eggs produced, because those plants are located in the same area of the cooperative farm, as compared to those in the first type of poultry group farm.<br>5. Under the over-egg production and production curb policy since recent five years, poultry group farm intended to have their own feed mixing plant in order to cut their feed cost and to market directly to retail store such as supermarket in order to save the egg marketing cost and to obtain higher egg prices.<br>It should be important that the poultry production and marketing system are reorganized efficiently in order to cut the costs.