Principle of good faith. Protect the historical and cultural heritage in historical and cultural areas, protect historical and cultural blocks with relatively complete buildings in Ming and Qing Dynasties and buildings in the Republic of China as the main features, and important historical sites related to folk cultural activities, and continue the historical development of traditional culture as a whole.

Principle of authenticity. Protect the real historical information such as urban texture, spatial layout, block scale, cultural relics and outstanding historical buildings in historical and cultural areas, and maintain the rich historical and cultural connotation of the city.

The principle of sustainability. Improve the function, renovate the landscape, improve the living environment, make the historical buildings and their environment not only maintain their style but also meet the needs of modern life, and improve the overall quality of historical and cultural areas.

Principle of classified protection. According to the different historical and artistic values of historical buildings, the different degree of preservation, the different types of urban space and environmental characteristics, the corresponding protection regulations and remediation measures are formulated to maintain the diversity of historical features and make the planning operable.