: In this paper, we propose an MDA based approach for developing multi-agent systems. MDA specifies a structured software development process divided in modeling stages. In the PIM stage, where platform independent models are specified, we propose to use an MAS modeling language called MASML since it does not restrict or specify implementation platforms. In the PSM stage, where platform specific models are defined, we propose to use the UML modeling language. The MAS-ML models defined in the PIM stage are transformed into UML models at the PSM stage, based on an object-oriented framework for implementing MAS. In the last stage, the application code is generated from the UML models.