Abstract: With the high quality development of railway engineering construction, the demand to Building Information Modeling(BIM) automatic generation technology for autonomous modeling of railway BIM is increasing day by day. Taking railway passenger station as an example, according to the engineering demand characteristics of automatic transformation of two-dimensional drawings to generate BIM, this paper put forward the main contents of BIM automatic generation technology system from the aspects of data acquisition, transformation, component matching and model optimization. Based on the data reading, vector graphics recognition and graphics patrol fuzzy recognition technology of Data Exchange Format (DXF), the paper proposed the storage mode and extraction method of key information of two-dimensional drawing. Based on the logical relationship between BIM components, the paper proposed the two-dimensional to three-dimensional, rapid layout and optimization technology of standard component model. The results show that the application of the above technologies in railway engineering construction projects can improve the efficiency of BIM modeling and improve the quality and level of railway engineering management.