Abstract: The policy-processing of grid construction refers to the attainment of agreement between the planner of grid construction and interest groups of external environment. This agreement will guarantee the smooth progress of grid construction. These external environmental factors include: compensation for expropriating civil lands, house relocation and resettlement, compensation for removing attachment on the ground and possible hazard of unearthing underground tubes, compensation for both temporary and restrictive expropriation. The policy-processing of grid construction involves highly numerous and complicated group interest, for the complexity and multi-tier of motive in the behavior of every interest group. So, to depict the characteristics of interest groups, The paper makes an economic assumption of all interest groups concerned with the complex external environment in the construction of grid, by setting the policy-processing of grid construction as the game between the land expropriation and its compensation by the grid company, local government and local residents. As a project of public interest and exhibition of land transfer and governmental imperative force, the policy-processing in grid construction is generally commissioned to local government to negotiate with local residents in terms of compensation for land use. It is the target of the grid company to fulfill its social responsibility and lower construction cost, on condition that the construction project is not affected. The local government aims to coordinate economic development of the local life with its social equivalent, improves the related infrastructure and performance of government officials. Local residents call for a high standard of compensation for grid-construction land expropriation and environmental pursuit. Failure to strike a balance between any two of the three parties will lead to difference in behavior. By using the thought of Rubinstein alternating offers, the paper simulates the game process in the policy-processing of grid construction, and constructs the Principal-Agent model given the incomplete information for grid company and local government. This paper also discusses the game model for the bargaining between local government and residents and makes an analysis of the mutual action among the three interest groups: grid company, local government and local residents. Probe is made into the achievement of balance in the allocation of benefit for all interest groups under the current policy. The last discussion aims to construct a harmonious external environment for grid construction. Three conclusions are made as follows:（1）Government should take a lead in the policy-processing of grid construction. The role government decides to play and interest relationship has a direct influence on the legality of grid construction and the reasonable utilization of resources in construction.（2）Make sure that local groups and residents are informed of and involved in land expropriation. This will come before the reasonable compensation for local residents.（3）The optimal mechanism of impetus in the policy-processing of grid construction is the contracted responsibility system by the local government. The construction and perfection of interest balance in land expropriation will contribute to the macro-target of the grid company.