Abstract: The basic problem of safety management is accident reason, prevention and control. This paper begins with analysis of accident reason and suggests that the reason of accident, in macroscopic view, is indefinite and can not be sure. In order to prevent accident, we have to pay attention to the main accident factors and give consideration to microscopic factors at the same time. In an entertainment, the main accident reasons are technology factor, education factor and information control factor. The three factors constitute the triangle of accident prevention and control. The triangle, together with the formula of individual injury rate, can be used to explain the accident reasons and to find the methods to prevent accidents which are applied in safety management. Finally, the paper ended with conclusion.