The objective of this research aims at how to establish a complete and safety management system in plans. A set of questionnaire is established based on the framework of Taiwan Occupational Safety and Health Management System (TOSHMS) with additional factors from various literatures. After a rigorous statistical study on the reliability and validity of the test data, 43 key factors are relevant to the formation of safety culture of the plant in study, which also concluded 15 different cultural dimensions. Explanations of the results were discussed, and inter-relationships among safety factors were further explored and interpreted. At the end, a simple yet practical decision method called the Analytical Hierarchy Process is utilized to establish the comparative importance (weight) among the 15 cultural dimensions. Three major trends are discussed in this research: one for the two working groups (operating personnel and subcontractors) differs in safety cultures. Another for the six factors, which inclusive of personal background (education, seniority, age and position), workplace risk, security and satisfaction, in safety cultures. The other for decisions of consensus differs in safety culture. As a result, measuring current safety culture in steel industry and making a further explore between the causal relationships and cultural factors, so as to identify high risk working group in contract culture of the steel industry and find out the danger point of safety culture.