Effective and accountable procurement fund management is a key factor in supporting the smooth operation of a company, particularly in the railway transportation sector, which requires a rapid response to operational needs. PT Kereta Api Indonesia (Persero) has implemented the Temporary Advance Payment System (UMDS) as a funding mechanism to meet urgent operational needs. This study aims to analyze the implementation of UMDS in supporting procurement fund management at the Signaling, Telecommunications, and Electrical Unit (Sintelis) of PT KAI Daop 8 Surabaya. The study employs a qualitative descriptive method with data collection techniques including observation, interviews, documentation, and literature review. Data were analyzed descriptively through the processes of data collection, grouping, and interpretation. The results indicate that the implementation of UMDS has proceeded in accordance with procedures through the stages of preparing the Cost Estimate (RAB), verification, approval, fund disbursement, and the preparation of the Accountability Report (LPJ). The UMDS contributes to accelerating the fulfillment of operational needs, improving procurement efficiency, and supporting transparency and accountability in fund management. Challenges identified include budget constraints, administrative delays in the LPJ, and technical system obstacles, which were addressed through inter-unit coordination, administrative oversight, and regular system maintenance.