This paper was researched city recycling for mertro-city in busan contrast with cases of singapore. In this study, the city recycling plan of busan have several problem as global mega-city competition. To make rebuild of advanced mega-city, first, old metro-city in busan have to mixed industries and living area in city. Second, capital will have to flow into the city for development of global economic city. So it needs to be increased the resident population and floating population. Third, this city faced to change from past cases to new development approach strategy by compact city projects. Additionally, in citizon opinion research of busan, they have been recognized to increase old economic power by metro city recycling and special globalization project in old metro-city as more important issue. In conclusion, this paper reported busan have to deal old metro-city recycling issues with city competition strategy compare to many case of Singapore. From now in case of recycling in metro-city that will be promoting to complexed of business site & living area for return of young resident. And recycling plan in metro-city government side have to project fully including of diversified citizen opinion.