Abstract: Fron now on, newly-built railway lines will gradually decrease while the upgrade and reconstruction projects of the existing railway will increase constantly in China. So, it is urgent to speed up the standardization research on the interfaces of signal systems. EULYNX (European Imitative to Linking Interlocking Systems) is committed to formulating the standard of the interfaces of signal systems, thus laying a favorable digital foundation for the upgrade and renovation of signal systems in European railways. This paper introduces the EULYNX signaling data model and briefly describes the composition of signal systems in the model and its data preparation process, and gives detailed description on the data requirement definition process, the UML modeling process as well as the application flow of this data model. Compared with unstructured approaches, the EULYNX signaling data model is formal and convenient for users to browse the data model on the web page, enables flexibly extract and handle the data in the model by using software tools, and supports the direct generation of high-level language code via tools. In addition, the EULYNX signaling data model has the characteristics of visualization and standardization, which is conducive to the cooperation between relevant parties of a upgrade or reconstruction project of the signal system based on the same data model, thus ensuring the consistency of requirements and implementation, and facilitating the seamless data exchange in the whole life cycle of the signal system. The signaling interface standardization method established by EULYNX can provide an important reference for the future research of signal system interface standardization of existing railway lines in China.tem interface standardization of existing railway lines in China.