Abstract: In recent years, chemical simulation systems have been widely used in operator training, chemical parameter optimization and implement of control strategy. However, it is difficult to evaluate the result of operator training, chemical parameter optimization, implement of control strategy objectively and comprehensively. In the study, an ontology-based automatic scoring framework is proposed for chemical simulation system. A scoring ontology is built in the framework for sharing and reuse of knowledge. Basing on the scoring ontology, the framework can supply evaluation of operation, performance of control loops, safety, production and consumption in the simulation system. The case study proved the efficiency, objectiveness, comprehensiveness of the framework.