Embodiments of the present application provide an intention classification method, apparatus, and intelligent question answering method based on a service corpus. Intent consists of categories, user interrogations, and reply sources. In the intent classification, the intent category is set according to the business requirements; According to the category of the intent, setting user interrogationsmatching the business requirements; Setting a reply source for the intent, the reply source is associated with a corresponding knowledge base in the business corpus, a knowledge category or item, making intent and business corpus logically independent of each other, through the intent of the user question and the reply source and so on to form a corresponding relationship, After this correspondence is established, The process of using business corpus to train intelligent question answering system becomes the process of intent training of intelligent question answering system, which enables intelligent question answering system to accurately identify user's intent from user's questions after training, give more accurate answers to questions, and improve the response friendliness of intelligent question answering system.