The study of the modern age period folk house is still insufficient in the Korean folk house study. The study subject had a tendency towards mainly on the plan in the field of the traditional folk house which had been studied relatively lively. We were going to grasp the formation and the actual situation of the folk house in this paper targeting at Yeosu city where the folk houses were left relatively a lot. Specifically, we examined it how the composition and dimensions of timber framework changed according to period. The division of period from before 1910 to the 1960s classified it at 4 periods on the basis of the sociocultural change. However, as a result of investigation analysis, the change of the composition and dimensions of timber framework was classified at 3 periods not 4 periods. The division of 3 periods is “traditional era”, “modern age 1”, and “modern age 2” not “traditional era”, “modern age”, and “contemporary age”. The folk house group came as a common name for folk house without doing the division of period until now. There is a meaning in that this paper subdivided the period of the folk house group by the change of the timber framework technology. The timber framework is the effective index to investigate the actual condition because the change is difficult after building. Therefore, we examined it including the dimensions as well as the composition of timber framework in this paper comprehensively and systematically.