This paper with the purpose of protecting visual landscape environment in historical and cultural districts,analyzes categories and characteristics of historical and cultural districts from the perspective of visual landscape,finally with the assessment basis of "landscape picture" proposes the classification of areas of 5 different levels,that is,the optimal viewing gallery,the secondary viewing gallery,the optimal viewing surface,the secondary viewing surface,and the common viewing surface,explores an approach of evaluating pollution indexes in historic and cultural districts by comprehensively evaluating "landscape pictures" in those areas of different levels.
