Since 1995 the special act for safety management of public facilities have been enacted in Korea. Since then undergoing safety accidents great and small, legal system was revised several times for safety promotion. As part of its efforts Korea Infrastructure Safety & Technology Corporation have periodically evaluated the building safety inspection or diagnosis reports based on Special Act for Safety Control of Public Structures and published annual casebook. This study investigates and examines the cases of bad or poor reports until now. This paper aims at reasoning out the technical and institutional improvement plan for error-prone problems when safety inspection of buildings.