Abstract: Expert systems and neural networs are two principal developing fields of artificial intelligence. They have made both great progress and success in the last decades. However, each of them has its own drawbacks and can not deal with complex engineering problems. So, it becomes a very important research field with great practical values and broad developing prospects to research on intelligent hybrid systesm based on neural networks and expert systems. In this paper, the characteristics of expert systems and neural networks are analyzed, a survey of intelligent hybrid systems is made and some problems are proposed.