The query interface integration is the key technology in realization of Deep Web information integration. However the bottleneck problem is the solution of differences and conflicts of query interfaces. TheThe most existed query interface integration work mainly focused on the conflict of attribute labels and attribute value, but there are many kinds of conflicts between interfaces because of the special nature of interfaces, such as attribute set structure conflict, attribute requirement conflict and so on. Ignore these conflicts will lead to incomplete and inaccurate integrated interface. Based on the query interface features, this paper presents the formal definition of interface, gives the framework for classification of the conflicts in query interface integration, and for each kind of conflict there is a corresponding solution strategy that lays a good foundation for interface integration.