The port, differently from general working place, is a closed area to execute security, customs, and quarantine procedures. The loading and unloading is being done differently by cargoes, ships, berths, and equipments. To load and unload a lot of equipments and different types of labor are required, in which work flow is very complicated. As above mentioned the port is very unique and deteriorated working place including danger. The purpose of this thesis is to propose ways to analyze and establish the preventive measure for cargo handling accidents in port. We have collected 923 accidents happened at Incheon Port during the period from 1994 to 2003. And to analyze and establish the preventive measure we have employed an advanced 6sigma DMAIC technology presently in spotlight as the best tool for management innovation. For the purpose of effective safety management of cargo handling in port, this thesis will help to revise and establish the law, system, standard, and standard working manual with respect to the port loading and unloading system. Now frequency of cargo handling accidents in port is highest for the second time among all industries, so we proposed the new safety management system to substitute port safety committee and to take full charge of safety in Ministry of Maritime Affairs and Fisheries.