Urban and rural land use change and associated driving mechanisms represent an active field of research in China and abroad. China is experiencing rapid urbanization and expansion of newly constructed land. Specifically, over the last decade, there has been a 78.5% expansion of urban built-up areas, which poses many potential environmental problems. Understanding the processes and driving mechanisms for the expansion of built-up land is conducive to prudent urban planning and management policies. In this study, the Xi'an metropolitan area was approximately divided into the city proper, township region, and rural areas based on various factors such as population size and the percentage of built-up land.We monitored variations in the trajectory of the built-up area and associated driving forces in Xi'an City for the last 35 years by using the Window Analysis Method combined with an expansion index.The results showed that the built-up area in Xi'an increased from 81787.3 hm² (8.1%) in 1975 to 107171.8 hm² (10.6%) in 2010. Temporally, the built-up area expanded at an increasing pace. The rate of land change was 173.11 hm²/a from 1975 to 1990 and 1139.39 hm²/a from 1990 to 2010, with the highest expansion rate of 2995.82 hm²/a occurring from 2000 to 2005. Urban and rural spatial differences in land use change were noticeable. Spatially, the central part of the metropolitan area increased more than the surrounding rural area.Built-up land expansion in Xi'an is a complex process subject to multiple factors at various scales. At the macro-scale, geomorphology is a limiting factor for built-up area expansion, i.e., the built-up area was mainly distributed over low terrain initially, followed by the development of tablelands on the higher mountain ranges and the lower river valley. Furthermore, population size and per-capita gross domestic product (GDP) also played significant roles in the pattern of development in the built-up area. At the landscape scale, education facilities, roads and wetlands/parks exerted profound influences on the shape of the built-up land. with Beijing and Shanghai, Xi'an underwent urbanization at a more moderate rate. With a long history of 6000 years and status as the capital city of China for more than 1200 years, Xi'an should not be further developed homogeneously; however, any newly planned construction should give full consideration to the ancient city style and aim to preserve historical relics instead of antique building. Furthermore, urban sprawl should be prohibited in the Qin-ling "forest zone" to the north of the city and the Wei-he River wetlands. Education is a key factor that shapes social and economic structures, with several university towns having become established in this region, in addition to the original southern suburb education agglomeration. To protect high quality farmland, we advise that strict land requisition bans be implemented on cultivated land neighboring the city. It would also be beneficial to improve the efficiency of urban construction projects, strengthen the scientific urban planning process, and avoid excessively encroaching on protected ecological resources. The Guan-zhong Plain, where Xi'an city is located, was the birthplace for Chinese culture. In recent years, the built-up area of this city has spread at a steady rate, which poses serious threats to cultivated land and food security over the long term. Thus, land resources in both urban and rural areas should be managed and configured by coordinating them as a whole.