This project of locating three government administrations; the Ministry of Knowledge and Economy, the Ministry of Education, Science and Technology, and the Ministry of Culture, Sports and Tourism which will be located in 2-2 District as a part of second phase construction for Sejongsi Govern¬ment Office Building; is an independent program and at the same time it is subordi¬nated program by the massive master plan. Therefore, the success of this project was to find design elements consisted of harmony between functional and morphological that embraced the whole and partial. To solve this task, three elements of Flat City, Link City and Zero City which is the key concepts of master plan was developed to actualize a place of symbiosis combining government office building and citizens as one through ‘Hangbokmaru – Happy Floor’ a theme of people, urban and nature. For the layout of continuity of the whole government office building, the most important facility, it was important to give a symbolic meaning as the point of start and end; to comply with the composition principle of Continuous Tangential Line for securing continuity of a super ordinate concept; to have facility layout plans for securing continuity of sur¬rounding contents; to establish site plan with a principle of vertical and horizontal connection plan of urban green axis. Also to give creativity only in 2-2 District, main connective passage that acted as a gate¬way image of the government office build¬ing was provided; and established scenery and security plan through landscaped hill; and proposed sloped elevations and natural lighted corridors, crossed ventilated struc¬ture and atrium to realize energy saving eco-friendly building. The working environ¬ment was improved by introducing natural lighted corridors and the entire office spac-es facing south, and the bottom space of piloti was proposed as 6th façade of which wayfinding and experiencing various spaces and a place of furnishing information were planned. The rooftop garden was composed of experiencing programs such as exhibi¬tion, education and resting, and in three-dimensional space. This project will be a significant project that proposes new urban scenery as completing over the master plan of Sejongsi Government Office Building by reinterpretation of its master plan.