Abstract: The alarm points given in process industry are massive and complex that may lead to trouble in monitoring the production. In combination with the characteristics of alarm system and matter-element analysis, a matter-element model was established for each alarm parameter, the correlation function was defined between alarm parameters and alarm levels, the weight certainty was improved based on the correlation function, and the comprehensive correlation function between alarm parameters and alarm levels was calculated. Starting from the premise of safety in production,the alarm parameters were optimized and chosen based on the value of comprehensive correlation function. Then the alarm optimization method for process industry was developed. The provided method was applied to the alarm system of purified terephthalic acid (PTA) solvent dehydration tower. The effectiveness of this method was verified by the result of the above case study. It showed that the alarm optimization based on the matter-element analysis reduced the number of alarms and alarm frequency, and provided a new way to alarm management and operation optimization.