The study dealt with in this report is intended to establish a method of morphological analysis for an objective apprehension of regional characteristics and the direction of the pattern transition of house plan types. Firstly, we introduce a means to classify them into a limited number of patterns given by use of diagrams (arrangement-, adjacency- and linkage-pattern schemes) which enable the arrangement, adjacency and linkage of unit spaces systematically to be generated. Then, we note that some definite regional characteristics of house plan types can result from analyzing interrelations of the relevant patterns. Lastly, we present the outline of our method of examining probable directions of pattern transition, being based on regional characteristics of plan types provided by the above pattern-analytical approach. The current approach has been developed to be used in our case study of examples in Hokkaido and Tokyo of ready-built dwelling houses.