Abstract: Interpretative structural modeling (ISM) is introduced to analyze the level and sequence relationship between the control actions, and then the analytic network process (ANP) is used to consider the dependent relationship between the control actions, to calculate the objective weight as a new Detection values, and then the calculation of the new RPN is carried out. Taking the poor furnace welding process as a study case, the difference between the new method and the traditional method is compared, and the different results of priority improvement order are obtained and the effect improved.