Abstract: urban geological survey is the leading geological work supporting urban planning and construction management. It is a vital role in urban geological safety, resource guarantee and safe operation. How to carry out urban geological survey, clarify the survey content, survey accuracy and depth, fine exploration and safe utilization of underground space, and how to support services are the key to do a good job in urban geological work. This paper combs the progress and degree of urban geological work in China, focuses on the urban geological survey of Guanzhong Plain Urban Agglomeration and Xi'an National Metropolis, discusses in detail the connotation, accuracy and application of urban geological work in Loess covered areas, and tries to summarize the role and existing problems of urban geological work in supporting land spatial planning in Northwest China, so as to further guide urban geology in Northwest China.