This study aims to examine the transitional process and its effect of Okcheon Jaesa in Yeonghae, Kyoungbook province. Through various bibliographies and Jaesil building in Yeonghae area, the results of this study are as follows: 1) Okcheon Jaesa was established in early 17th century at latest, since then it had been relocated several times. And it was estimated that it was relocated finally to its current location in 1725. 2) Hwasooroo was constructed in 1753, but it was destroyed by a fire in 1811. It is estimated that it was restored next year and remained so far. 3) The closed feeling of space of courtyard in Okcheon Jaesa is estimated as a result of replacing existing lecture hall into the lecture hall with elevated pavilion. 4) Andong-Kweon family affected on building of jaesil each other among their families through mutual exchange and competition. It is estimated to be the influence of Jipheeam of Mooan-Park family that Okcheon Jaesa was changed to Jaesil with elevated pavilion. Since then, Jaesil with elevated pavilion is estimated to have had effect on building Jaesil with low-columned elevated pavilion in Yeonghae area.