Abstract: In this paper a component-based simulation technology is brought up. This component-based simulation environment is based on the DEVS (Discrete Event System Specification) formalism and Sun's JavaBean technology. The DEVS provides a means of specifying a mathematical object called a system. JavaBean technology allows the modelers to drag and drop the software components visually and to combine specific JavaBean components to build their software. This paper introduces the DEVS-JavaBean simulation environment that contains basic JavaBean components of DEVS so that a modeler can visually change bean properties and relationships between JavaBeans. The reusability of components saves modelers in the model development time. In addtion, the convenience of JavaBean components such as drag-and-drop and visual modeling makes our simulation environment easy to learn and use.