This study is for recognizing the importance of the hygienic situation in operating of mass service. The food service industry needs to search more hygienic and safer management system through the application of HACCP system and provide foodstuffs which is much safer and more hygienic to the customer. To help hygienic improvement of mass service and HACCP application, we drew up the question item regarding each variable and collected a data through the research. The research was done to the worker who works for mass service and executed at the staff dining room inside the company of Ulsan. The result of research is following. First, the question about the awareness of HACCP among workers of mass service is examined the application of the HACCP is necessary to mass service. From this item, we find that the standard HACCP becomes the important element in hygienic improvement of mass service. Second, the question about hygienic control level (condition) was invested the personal hygiene is managed best and the hygiene of enterprise funeral facility and the machinery and tools is managed better. Third, the item regarding the customer trust about the ready-made food appeared it gives a trust to the customer the personal hygiene of the HACCP application enterprise market staff and even the HACCP application enterprise funeral staff behavior pattern weigh with a reliability.