Abstract: Data structures selection and Route Search Algorithm are two key technologies of computer interlocking software. Because the common data structure constraints to interlocking software, and route search algorithm affects search efficiency, this paper optimized the Route Search Algorithm based on station type data structures, used the example of yard as the object to discuss the researching course for basic route and alternate route by using Height Search Algorithm in detailed, which showed that the Height Search Algorithm overcame shortcomings of Breadth and Depth Priority Algorithm, the search goal was specific and the search course was high-efficiency and accurate.