With the increasingly challenging problems of urban environment, urban environmental planning as a primary means of prevention, which plays a leading role to solve the disorder, blind and random of urban environmental protection and socio-economic development and make the urban environmental protection in an orderly manner. In recent years, with the increasingly pressure of urban environmental carrying capacity, the urban environmental situation of Xi'an is not optimistic. While the Xi'an environmental planning has made some effect, in practice, there are still some problem such as the legal status, the legal nature and the legal value are not clear, the legal validity has not receive much attention and the public participation is not enough. It makes the effects of urban environmental greatly reduced to some extent. Therefore, we must strengthen the legal system, improve protection mechanisms and take such other measures to the urban environmental planning, so that Xi'an environmental planning could play an effective role to ensure the sustainable of city.The paper based on the survey and statistics of Xi'an, collated the existing laws and rules of environmental planning, analyzed the situation of all stages of urban environmental planning and found the problems in practice. Then it proposed the development predicament of current urban environmental planning. Meanwhile, it considered that the main reason is the lack of legal theory and environmental planning legislation. And further more, it deeply analyzed the basic legal issues of Xi'an environmental planning from three dimensions of the legal nature, legal value and legal validity. According to the different characteristics of the dynamic and static meaning, legal nature of urban environmental planning has been specifically analyzed; The basic legal values of the traditional order, freedom, efficiency and justice has been expanded and trimmed; And from different angles of public force, deterministic force, binding force and execution, the legal validity of Xi'an environmental planning has been discussed. And from the theoretical level and system level, the measures of legislative construction for constantly improve the Xi'an environmental planning has been proposed. It has an important theoretical and practical value. |