Supplier’s assessment criterion in the supply chain is an important consideration. Suppliers, who have established qualified assessment criterion would be able to maintain the stability of quality and reasonable price, so on. In recent years, because of the realization of the importance of environmental protection, when a material supplier is chosen, it is necessary to consider whether the material supplier satisfy the requirement of environmental protection criteria. Therefore, this study considers about supplier selection and quantity distribution issues, and uses multi-objective mathematical programming model to optimize the solution, and also uses Pareto Genetic Algorithm (Pareto genetic algorithm, PGA) to obtain the best decision, through analyzing the result of this case study we can achieve the best design and are able to obtain enterprise’ targets.