To understand how to effectively manage a desert steppe environment during aperiod of warming and nitrogen deposition,the effects of nitrogen(N)addition and warming on the community structure and diversity of cultivatable fungi were studied.The dilution plate method was used together with the molecular analysis of 18SrRNA after the application of infrared radiation to simulate global warming and fungi were artificially fertilised for 6years in a desert steppe with the dominant species of Stipa breviflorain Inner Mongolia.The results indicated that 17fungal genera were isolated from the desert soil.N addition alone or with simulated warming led to a significant(P<0.05)increase in the total number of cultivatable fungi from 6.70*10~5 colony-forming units·g~(-1) in the untreated control to 1.45*10~6 or 1.92*10~6 colony-forming units·g~(-1),respectively.Moreover, the community composition and dominant species changed with N addition.With N addition alone,the dominant fungal genera Aspergillus,Hypocrea,and Cladosporium were replaced by Fusarium,Alternaria, and Pseudogymnoascus,and the species richness,evenness,and diversity significantly increased.The effect of N addition with simulated warming increased the abundance of the dominant fungal genera Penicilliumand Aspergillus, and another three dominant fungal genera were replaced by Fusarium,Alternaria,and Chromocleista. Combining N addition with simulated warming had no significant effects on the species richness,evenness, and diversity of cultivable fungi,compared with N addition alone.