Abstract: Oasis cities are the most important types of cities in Xinjiang. Most oasis cities are on the edge of the alluvial fans, which gives them similar environmental geological conditions. The cities have relatively rich and steady water resource and advantageous hydrogeological conditions for water supply. The geological conditions of building and communication are good. The available land of the cities is wide. But the disadvantages of the oasis cities are evident. The water resources are easily polluted. The cities are frequently influenced by the natural hazards, for instance, flood, earthquakes, land slides, debris flow. The balance of the natural environment is easily destroied. In order to develop the oasis cities, urgent measures must be taken to protect the oasis ecological environment and the desert around the oasis, to use the limited water resource reasonablely, to keep the water and land from pollution and to control the scale of the cities.