This paper deals with the administration on outdoor advertisements in Ibaraki prefecture. They partly entrusted the municipalities of which prefectures fundamentally have authority. This study is intended to be an investigation of the actual state of municipal administration on outdoor advertisements, and aims to clarify how to observe problems involved in decentralization. As a result, ... [Show full abstract] followings became clear. There is a limit in controlling outdoor advertisements with the ordinance of Ibaraki prefecture. Some municipalities positively expect the delegation of authority. As for Ibaraki prefecture, each municipality has the potential to play an independent role in administering outdoor advertisements.