Despite Today’s bold presence of machinery and the progress of technology in societies, human’s safety, and occupational health are still under the shadow of numerous hazards. In order to ensure sustainability, in different sectors of industries, occupational health and safety must be observed diligently and businesses have every reason to be concerned. It is estimated that annually 120 million injuries, caused by work-related accidents, have led to 220 thousand death reports all over the world. Therefore, Precautious measures should be taken in order to protect labor force against unfortunate repercussions, stemmed from the hazards of the workplace. In an overall sense, injuries and occupational accidents, are the result of a set of unsafety (actions and conditions). Therefore, accidents can be decreased in rate by identification, prevention and elimination of this unsafety. The main purpose of this research is to propose a system dynamics model to analyze dynamisms of safety management systems, occupational health and accident management. Using such approach, and with the aid of causal feedback loops analysis and stock and flow structure, we can define and conceptualize complex interactions within these systems. In this approach we model the structure of their relationships; and lastly, simulate their dynamic behaviors. Results show that implementing policies related to human factor engineering and promote safety culture and standardization in the workplace, were the major appropriate and effective solutions which can have a positive effect on accidents management, they can help to develop the health and safety management system. Also, among these policies, both safety culture and human factor engineering have significant impacts on decreasing the number of accidents, but from a long-term viewpoint, safety culture is the most effective.