In order to provide an effective approach to assisting decision makers to choose between realistic alternatives on the shop floor for Green Manufacturing, a decision-making framework model of machining process planning for Green Manufacturing is established from three aspects, including decision-making problem set, decision-making objectives and their mapping relationship. The considerations in traditional decision-making of machining process planning are quality, time and cost. But from the point of Green Manufacturing, the factors of resource consumption and environmental impact are considered also in this model. A new algorithm integrating Grey Relation Analysis and Analytic Hierarchy Process is proposed to aid the process of decision making, especially for the handling of the relativities of the objectives. A case study of the selection of machine tools for Green Manufacturing is given with the data provided by the industry partner. It shows the feasibility and effectiveness of the model and method presented.