Abstract: Node optimization in the network organization is a basic way to improve the competitiveness,and maximize the organizational effectiveness.Network organization is an open system,by joining and leaving the node enterprises,showing the characteristics of dynamic and non-linear.In order to ensure the network effectiveness,and enhance the ability to compete in the organization,how to adjust the node becomes a hot issue.In this paper,we will study on enterprise selection mechanism in the network organization.At first,based on entropy,we divide the node entropy into several factors,such as strategy,structure,environment and others,then use this evaluation index to establish the entropy evaluation model.Secondly,with synergetics,based on the organizational effectiveness,we use three dimensions of trust,business integration and sharing of knowledge to build organization and coordination mechanisms,then use order parameter model to analysis the evolution of collaborative degree of order,in order to develop a more ordered structure.Theoretical analysis shows that,this new mechanism of node selection can be better for the network effectiveness.