This paper presents an in-depth evaluation of the compatibility of public 5G macro stations with GSM-R (Global System for Mobile Communications – Railway) systems in high-speed railway environments. Given the critical role of reliable and efficient communication systems in modern railway operations, the integration of emerging 5G technology with the established GSM-R frame- work is of paramount importance. The paper begins with a comprehensive over- view of both GSM-R and 5G technologies, detailing their technical specifications, capabilities, and current applications in the context of high-speed railways. A technical analysis then contrasts these systems, highlighting their respective strengths and limitations. The core of the paper is dedicated to assessing the interoperability of 5G macro stations with GSM-R systems, identifying potential technical and logistical challenges, and proposing viable solutions for integration. Additionally, the paper examines real-world case studies where these technologies coexist, drawing lessons from their implementation. The implications of this integration for high-speed railway operations are thoroughly discussed, considering aspects of safety, efficiency, and operational reliability. Finally, the paper concludes with insights on the future of railway communication systems, emphasizing the need for further research in this rapidly evolving field. This study aims to provide a foundational understanding for railway operators and technology developers, paving the way for optimized integration of 5G technology in high-speed railway networks.