We examine if the incentive policies of prefabricated buildings in China are well distributed and if the policies reasonably match the development of prefabricated buildings. In applying a policy tools perspective, we will establish an indicator evaluation system of incentive policies of prefabricated buildings, which includes area award and construction link, financial, land, link, and technical support. We then use the Grey Relation Analysis Method to establish the evaluation model, which we then apply to evaluate and analyze the text data of incentive policies for prefabricated buildings in various provinces in the period 2016–2018. In drawing on the results of the evaluation model, we put forward policy suggestions that will promote the high-quality development of the prefabricated construction industry. These include the following: provinces should reasonably select or formulate incentive policies in accordance with their own actual conditions; governments at all levels should improve demand policies that are currently absent; they should also pay attention to the balance of incentive policies at all levels of the industrial chain and also increase the policy support that is currently available to the management personnel and operators of prefabricated construction.