Abstract: The IT products like as firewall, Intrusion Detection System (IDS) and Virtual Private Network (VPN) which made to perform special functions related to security are used to supply security characteristics. But the method using these products may be not the perfect solution. Therefore, when making some kinds of software products, security-related requirements must be considered. It is essential that not only the customer’s requirements for software functionality should be satisfied but also the security requirements imposed on the software development should be effectively analyzed and implemented in contributing to the security objectives of customer’s requirements. The secure software may be implemented by not only applying Firewall or IDS but also considering security requirement appended to customer’s requirement. In this study we propose a security engineering based approach considering security when developing software.