It is necessary for an organization to react to various changes from both the external environment and internal elements in multi-agent systems since existing open, dynamic environments. Reorganization provides the adaptive capabilities of an organization to deal with these changes and becomes one of the key issues of organization theories. To represent and simulate the dynamic process of reorganization in multi-agent system, in this paper, we propose a graph transformation based approach in the context of organizational structures and introduce a quantitative simulation of predator/prey game to show how the reorganization process can be enforced with this model and to indicate preliminary results of the reorganization simulation based on this graph transformation approach.