Question answering system can answer the users' questionsin the application of the precise and concise language. Question interpretation is the primary work of question answering. The precision of Question analysis has a great effect on the following processing work. In this paper, we present a new method of question interpretation based on the users' question theme and focus. This method by which the interrogative words, syntax analysis, question focus words and the first semenes of the question topic in HowNet have used as classification feature. Experiment result indicate that this method can bring about a better effect on improving the accuracy of the classification.