The electronic procurement (E-Procurement) system in Indonesia faces several critical problems such as low process efficiency, insufficient transparency, and a high potential for procurement corruption and fraud. This study aims to design improvement of Indonesia’s E-Procurement system that can minimize corruption and improve efficiency in the procurement process by using Business Process Reengineering (BPR) and Structured System Development (SSD) methods. BPR is performed by modeling and simulating current (As-Is) and proposed (To-Be) process. SSD in this study consists of four stages; the creation of Entity Relationship Diagram (ERD), relational tables, use case diagram, and Data Flow Diagram (DFD). This study provides three improvement scenarios to solve issues in the E-procurement system by implementing an integrated information system linkage across government agencies and a real-time bidding solution. The three scenario models' simulation has different solutions to minimize corruption and produce different cycle times for each scenario. Using the SSD method, the information system model is designed to support business process improvement with the best scenario.