Abstract: The strategy of solving problem in carburizing expert system is studied in this paper. In order to advoid subjective view and one-sidedness, multi-blackboard strategy of solving problem is proposed, which are problem blackboard, domain blackboard, argument blackboard and conclusion blackboard. The best conclusions of non-acknowledged problem are selected through the argument of multiple experts. This paper builds a theoretical framework of argument on the basis of propositional knowledge. The argument algorithms is designed. The results of simulation are satisfactory.