<p>As the largest desert in China, the Taklimakan Desert features unique mobility and alternating mega-dune and inter-dune landscapes with rich dune types. Most areas of the sand sea were explored in the early 20th century. However, the eastern Taklimakan Desert characterized by extremely tall dunes, had received little attention until 2022 owing to transportation inconveniences. This study examined the alternating mega-dune and inter-dune landscapes in the eastern Taklimakan Desert, through spatial analysis and field surveys. Results demonstrate that the tallest mega-dunes are distributed primarily to the east of the central desert, with the occurrence of approximately 240 mega-dunes exceeding 150 m in height. The height-spacing relationship of mega-dunes with different orders exhibits a weak correlation, suggesting that the dune formation and evolution are more complex than previously documented; this could be attributed to the factors other than solely the wind regime. Additionally, from the field survey, we found that sand availability is the dominant factor for constraining the sustained growth of mega-dunes. A pattern coarsening may be responsible for the development of the dune fields in the eastern Taklimakan Desert, thus yielding constraints on the development of mega-dunes, and other dune fields on Earth as well.</p>