Abstract: According to the confusion on the intrinsic safe flame proof system and the intrinsic electric power conception and the many inconvenie nces occurred in the related research and the product application process,a detail analysis and discussion was conducted on the category division a nd features of the intrinsic safe flame proof system and the intrinsic safe electric power.There were four intrinsic safe flame proof system structures concluded and established.A detail explanation and introduction was conducted on the structure features ,suitable applied location and other features of each category.During the summarization of the system structure process ,according to the electric power application location and the requirements of the system,the conception of the primary intrinsic safe electric power and secondary intrinsic safe electric power was introduced.A discussion was conducted on the design requirements and the applied conditions of the two intrinsic safe powers.Meanwhile a statement was made on the features and applied location of the front end protection and rear end protection modes for the intrinsic safe electric power.