In order to discuss sedimentary facies and sedimentary evolution of middle and upper Jurassic in the western section of South Qilian Basin. Lithological characteristics, paleontological characteristics and lithologic assemblage of middle and upper Jurassic in the study area were analyzed. The results show that the middle and upper Jurassic in the study area were composed of river diffuse, embankment, river bed deposition, fan delta plain, delta front and coastal shallow lake subfacies. Sedimentary facies studies show that Xingou-Xiangyang coal mine and Wausdosoka were belong to different sedimentary basins in Jurassic, respectively. And the differences of sediment facies are obvious, showing different processes of sediment evolution. In the middle Jurassic, the Xiangyang coal mine was mainly composed of meandering river deposit, the Xingou coal mine was mainly composed of fan delta plain deposit, and the area of Waustusoka was composed of shallow lake deposit. Late Jurassic, there were not deposit in Xiangyang coal mine, and the Xingou coal mine was mainly composed of the coastal shallow lake deposition, and the Wausdosoka area was composed of lakeside deposition.