Lichen is a kind of important biological resource of desert steppe at the eastern foot of Helan Mountain, Ningxia. The formation of the lichen crusts has made an important contribution to the stability of the regional landscape. The field investigation of lichens was carried out from 2014 to 2019 in the desert steppe of the eastern foot of Helan Mountain, and more than 500 speciemens were identified using phenotypic characteristics and DNA sequence analysis, both the species composition and biogeography were analyzed. The results showed that: (1) a total of 74 species belonging to 41 genera and 19 families were identified, with 2 taxa new to science (in press), 25 taxa and 11 genera representing new records for China, and 56 taxa new records for Ningxia. (2) The most important biogeographical element of lichen was north temperate element (33.78%), other main elements included Eurasian and cosmopolitan. The results showed that the area had a distinct north temperate character in floral composition. (3) Crustose and squamous lichens accounted for a high proportion (81.1%), which embodied the characteristics of the lichen species adapt to the local climate conditions. The field survey showed lichen habitats in the desert steppe of Ningxia Helan Mountain were very fragile. This study is helpful to improve the understanding of lichen species diversity and promote its conservation in the area.