There are still a number of “olles” existing with traditional alley characteristics in the inner city of Jeju. As a matter of fact, the renovation of old buildings and the protection of alley space are facing a dilemma due to the existence of less than 4m-width-roads in the area of "Mu-geun-sung". This study examines the current status of alley space in "Mu-geun-sung" area; and puts forward to the potential possibility and limitation of alley space regeneration via exploring the applicable scheme of building agreement. In the field survey, a number of regions in inner city of Jeju witnesses the existing majority of invaluable, conventional olles. So as to grasp the feasibility in "Mu-geun-sung" area, we designs a simulating experiment to carry out the Building Agreement; and compares with the current development model in this area. Building Agreement implies to establish gradually a separation of land ownership under the existing unified development of landowners and users, thus to explore a variety of land exploitation systems by separating land ownership and right to use land. As a result, the deterioration of the street landscape results from the increase of building storey numbers. The damages to the surrounding environment brought by the newly built buildings will be minimized as well as keeping the maximum building volume rate. Obviously, these measures will alleviate infringement to the traditional residential sunlight and privacy space effectively, and reduce the pressure from high-rise buildings to the alley space, so that the landscape of the alley will enhance to form a more comfortable alley environment.