Abstract: This paper analyzes the sources of law of EU environmental assessment at both international level and EU level to envisage an overall picture of the system. Then, problems of the EU environmental assessment system including implementation difficulty, integration paradox and some detailed shortages are investigated. Implications of the EUs system to China are explicated: environmental impact assessment and strategy impact assessment should be introduced and relevant practices are ought to be encouraged; the litigation in terms of environmental assessment need to be expanded; the role of local government in environmental impact assessment system should be emphasized.