To provide a safety assessment system capable of performing an efficient assessment by facilitating the input of design data or the input and accumulation of operating state, and stereotyping the procedure of an assessment method to enhance the using ratio of a completed analytic system software.

This system comprises a computer for storing a design file in which data related to safety adapted as the design condition of a product and the locus of responsibility related to the keeping of safety are inputted; a computer for successively inputting and tabulating data for abnormal state, maintenance and inspection sate and remodeling content including the operating state and accident of the product and accumulating and storing tem as a result file; and an analytic system having the step of collating the design file with the result file to compare the difference in contents, and displaying or printing the locus of responsibility retrieved from the contents, comparison result and difference, and the step of inputting contents requested by an operator according to it and further displaying or printing the retrieval and result.