This paper addresses legislation status of air route design standard of Korea. Korea Ministry of Construction and Transportation's Order Number 300 (March 28, 2001) prescribes that firstly, the design of air routes in Korea should be in accord with International Civil Aviation Organization(ICAO)'s recommendations published in Annex 11: Air Traffic Service and Procedures for Air Navigation Services: Aircraft Operations (ICAO Doc 8168-OPS, 1986), and secondly, United States Federal Aviation Administration(FAA)'s Terminal Instrument Procedures (FAA, 1976). An investigation on the current air route specifications of Korea reveals that they are in accord with neither ICAO's recommendations nor FAA's standards in that the width of Korea's air routes are narrower that the international recommendations and standards. As a member state of ICAO, it is imperative for Korea to follow the international standards. In that purposes, Korea should legislate and regulate the detail standard for air route design. For the legislation, FAA regulations are to be followed because FAA rules contains more detail specifications while ICAO recommendations includes allows a range of policy decisions, which may result in a confusion in practice.