Mineralogical maturity can well reflect the composition of clastic sediments, which is related to provenance, chemical weathering, transported sediments and climate. Therefore, it has become an essential geochemical index of major elements in desert research. In this study, sand samples were collected from 22 dune tops in the Gurbantunggut Desert and their major elements were measured. On this basis, the mineralogical maturity of the sediment was calculated using the method proposed by Pettijohn, and the mineralogical maturity characteristics of the desert sediment were systematically analyzed. It was found that the sandy sediments in the Gurbantunggut Desert had obvious zonal and distributional differences, showing an increasing spatial distribution trend from the desert edge to the desert hinterland. Factors such as physical sources, transport deposition and sorting processes, vegetation, and chemical weathering are responsible for the regional distribution differences.