This paper presents an integrated methodology for design and optimization of chemical process based on the green chemical principles, which inherently incorporates environmental factors into the chemical process synthesis. Firstly, the process environmental impact assessment method (EIA) is proposed, which includes two parts, the environmental impact of material flow and that of energy. Secondly, a multi-objective mixed integer non-linear mathematical model was established by considering environmental and economic factors. Finally, the high nonlinear model was solved by multi-objective evolutionary algorithm (non-dominated sorting genetic algorithm or NSGAII). The proposed methodology was highlighted through two DMC production processes, pressure-swing distillation and extraction distillation process.