The modular and scalable leverage planning for flexible platform is crucial for derivative product design. A multi-objective flexible platform leverage planning method with quantitative indices is proposed. Including customer requirement analysis and product attributes - components mapping, a platform planning process model is presented. The importance rate of product attributes and levels utilities of customer satisfaction are achieved with conjoint analysis. Quality function deployment is applied to acquire the co-relational matrix between attributes and components. Then the quantitative platform diversity index and commonality index are proposed to construct a two-objective leverage model and calculated by evolutionary algorithms to get Pareto optimal design solutions. The effectiveness of the proposed method is illustrated by the leverage planning for large-scale hydraulic support platform.