The amount of work involved in building medium and small size ships is relatively small, nevertheless, there has been a certain limit when it is attempted to accelerate and shorten the construction time. And in many cases, ships that are built in series are not of identical or similar type. If, under such circumstances, it is intended from the managerial viewpoint to maintain the planned production level and keep the amount of production work evenly balanced during the given period, the ships will have to be built by using several building berths. However, if a certain method is developed by which the amount of work can be kept constantly balanced even when building different type ships in series and furthermore some device of shifting hulls is developed, it will be also possible to fulfill the managerial needs using comparatively small numbers of building berths. So the auther here examines the number and the total length of building berths with their related facilities in the case of various construction methods for medium and small size ships, from the viewpoint of evenly balancing production work and the amount of ships to be built in shipyard.