Abstract: In complex mechanical product design, the disassembly, remanufacturing, environmental and other individual factors of the end-of-life (EOL) processing are considered. The time of product useful life might be shorten or the product might be discarded as useless, because of time and costs of the operations by recycling of materials and reusing of components. It also makes serious environmental pollution when components of products are improperly disposed. A mathematical model is established based on synthesis key-green-quality index which is composed of the operation efficiency, the economic costs and the environmental impact by the measurement and analysis of EOL processing. An optimization process using strength Pareto evolutionary algorithm 2+ (SPEA2+) is put forward on the foundation of the analysis and measuring of the characteristics of EOL processing. Based on the mathematical model of product optimization design for EOL processing, the Pareto set for the multi-objective optimization problem is obtained using the multi-objective optimization algorithm. The multi-objective Pareto-optimal solutions are facilitating operations of the EOL phase. The efficiency and effectiveness of the proposed method is illustrated by the green multi-criteria optimization for product design project of gearless traction machine

Key words: End-of-life, Green design, Multi-criteria optimization, Pareto set