Changes in commercial structure following the Great East Japan Earthquake Disaster are examined from organizational and spatial perspective. The study area is Yamada Town in Iwate Prefecture, Japan, which was severely damaged by the huge tsunami caused by the 2011 Great East Japan Earthquake. Supported by the municipality, three main actors─local minor retailers, local major retail companies, and major retailers outside the area─pushed through a restructuring of the commercial environment. Two commercial institutionalizing movements occurred during this process. One was led by a local major retail company, while the other was led by local small retailers with municipality support. In the case of Yamada Town, a local major retail company had a significant role in changing the commercial structure because of its financial power and human resources. This retailer established its business in local infrastructural facilities, including as temporary stores, and rapidly organized local retailers with its future business plans. In contrast, the municipality projects assumed a role in reconstructing the stores of other local retailers that had difficulty making management decisions about the future. Moreover, in suburban areas, local retailers supported residents. The spatial changes in the commercial structure may be understood from the perspective of regional structure, in terms of the central district, its suburban areas, and areas outside Yamada Town. The local retailers and the municipality organized a commercial hub in the central district. In addition, major retailers located large stores in suburban areas that were easily accessible. Moreover, large shopping centers in