The project management (PM) practices that characterize Project-Based Organizations (PBOs) are part of their core business processes. Moreover, some PBOs obtain their incomings by developing and delivering projects, such as construction companies. PBO's design and analysis have been developed from an organizational design perspective applying several frameworks such as Galbraiths' Star Model or McKinseys' 7S. For the same purpose, the systems thinking approach is also a suitable alternative for managing organizational complexity, computer-assisted business design and analysis. Within this perspective, the Enterprise Architecture (EA) managing tool has been widely applied in the information systems industry and, over time, has extended to other industries. EA is a group of principles, methods and models for designing and analyzing the enterprises' organizational structure, business processes, information systems and infrastructure. Systems thinking has positioned itself as a suitable perspective for organizing PM knowledge, as shown in the last version of PMBOK (seventh). Following this trend, this research develops an EA model of a PBO and shows how the EA components can represent the specific PM artefacts displayed in a PBO. The obtained model and its completeness is evaluated using the Star Model framework. This work is expected to encourage analysts and project managers to opt for EA as a management and governance tool for their projects and the organizations that host them.