Selecting plant communities of 27 typical sample plots in the eastern part of Qaidam Basin as research object, we analyzed the niche characteristics of 13 species of dominant plants in dimensions of soil moisture content, bulk density, organic matter, pH, total salt, total nitrogen through the niche breadth and niche overlap index calculation. In order to provide theoretical reference for vegetation restoration and ecological protection in Qaidam Basin. The results showed that: (1) the average niche breadth of the 13 species of plants on the soil of six factors in descending order is as follows: Ceratoides latens > Reaumuria songonica > Achnatherum splendens > Phragmites communis > Sympegma regelii > Salsola abrotanoides > Nitraria tangutorum > Kalidium foliatum > Kobresia > Ephedra sinica > Calligogum kozlovi > Tamarix ramosissima > Haloxylon ammodendron. Among them, the areas vegetated by Ceratoides latens had the highest in soil moisture content, bulk density, and organic matter content, and those vegetated by Reaumuria songonica had the highest soil pH, total salt content, and total nitrogen content. (2) The species with large ecological niche width did not show the greatest overlap among their ecological niches; instead, they showed a moderate overlap. (3) Ceratoides latens and Reaumuria songonica occupy a relatively high position in terms of both the niche width and niche overlap, and they play an important role in community construction. (4) For each of the 78 species pairs, the proportion of the ecological niche overlap in each soil factor less than 0.3 was 76%. In the eastern part of Qaidam Basin, the overall ecological niche overlap of the plants was low, which implied that the competition is small and the communities are in a relatively stable state.