The purpose of this paper is to establish a complete appraisal system and study on comprehensive environment risk assessment of brownfield reuse in procedure and method through the case of Xishan District, according to life cycle theory. Methods employed include system analysis, analytic hierarchy process and grey evaluation method. The result shows that,(1) The life cycle of brownfield reuse can be divided into three stages which are the confirmation and preparation stage, the control and treatment stage, the maintenance and supervision stage, including policy and legal risk, economic risk, organizational risk, pollution risk, etc, eight elements.(2)the environmental risk of Xishan District is in medium level. Additionally, due to the polluting and complexity of brownfield, it should be respond to the necessary control. It is concluded that the comprehensive environment risk assessment of brownfield reuse has high scientific and practical by using analytic hierarchy process and grey evaluation method.