Abstract: The development of mechatronics and current situation are discussed. It is pointed out that mechatronics system design is necessary. Mechatronics interface technology comes into being. On the basis of analyzing and studying the mechatronics system, the construction of mechatronics system is proposed. By researching the mechatronics system's components and their relationships, the concept, function and classification of mechatronics interface technology are given. Mechatronics interface technology is a new method to design the mechatronics system. Therefore, the developing trend of mechatronics interface technology is to realize its intelligence, standardization, miniaturization and personification.