This research is titled " Optimizing Refinery Oil Accounting System (ROAS) Master Data Through Integrated Web Procedures and Master Supply And Sales Control System (MY SSC) at PT. Kilang Pertamina Internasional Refinery Unit IV Cilacap." The aim of this study is to develop an integrated web procedure to manage ROAS tank master data and integrate it with My SSC. The data collection methods include primary and secondary data. Primary data were obtained through interviews with finance workers and Intake Output supervisors, as well as field observations. Secondary data were obtained from archived documents and literature studies. The results show that the integrated web procedure improves the efficiency and accuracy of data management, supporting operational processes and decision-making at PT. Kilang Pertamina Internasional Refinery Unit IV Cilacap. Therefore, web technology and My SSC integration are highly beneficial in optimizing ROAS tank master data.