Since few studies consider the influence of interaction on the project portfolio dynamic selection, the conception of project interactive coupling networks is proposed based on the complex network theory with interaction effect. The definition is described from six aspects, which are project profit, cost, risk, states, interactions and strategy fit. Then based on this, we propose generation and adjustment rules of the network, define the stable state and develop this network. The research shows that compared with the traditional optimization model, the portfolio got from the project interactive coupling network is better. It can use resources more efficient, avoid risks and increase benefits. Moreover, the project interactive coupling network can be understood better, which can give some support to project portfolio management. Project portfolio managers should protect and support the projects with high betweenness centrality and clustering coefficient, which are the core projects in a portfolio, in case the failure of these projects will lead to failures of their neighbour nodes or even a cascading failure of the project network.