The purpose of this paper is to clarify the spatial formation and the functional layout of market towns, Sasanami-ichi and Akiragi-ichi along the Hagi-okan. The results are as follows; 1) The both market towns of Sasanami-ichi and Akiragi-ici were formed in the early Edo Era. 2) The houses of Sasanami-ichi were invariable through the Edo Era. 3) The houses of Akiragi-ichi increased step by step during the Edo Era. 4) In Sasanami-ich the lodging, business and transportation functions were respectively arranged in Kami-no-cho, Naka-no-cho and Kudoshi. 5) In Akiragi-ich the lodging and transportation functions were arranged in north and south side of Hagi-okan street, and the business function was scattered in Akiragi-ichi.