As the complexity of software development is increasing due to networking, multimedia, and diverse system architecture, the need for effective software development methodology is increasing. Especially, due to software standard and internalization of software market, it is necessary to accept international quality such as ISO 9000-3. In addition, object oriented development methodology is required due to rapid propagation of OO technology and standardization. Recently, UML was accepted by the OMG as standard object-oriented modeling language for distributed environment. When we UML was accepted by the OMG as standard object-oriented modeling language for distributed environment. When we develop Java and CORBA-based software, often UML is applied to Java and CORBA-based projects. However, current structural or OMT-based object-oriented methodologies. In this paper, we proposed UML-based development and concrete guidelines for each phase in order to apply UML to software development practically and effectively. Also, we define the transition guidelines and semantics between various development tasks. In addition, the analysis and design techniques of user interface and system development techniques needed in Web application development are presented.