Winter rapeseed is an important oil crop and winter cover crop in north China. To investigate the composition of rhizosphere soil fungi community and the ecological benefits of fungi driving and influencing soil fertility in different winter rapeseed (Brassica rape L. and Brassica napus L.). The microbial community composition, soil enzyme activity and soil physicochemical property in rhizosphere and non-rhizosphere soil of winter rapeseed were analyzed and compared. The results showed as follows: (1) The rhizosphere microbial biomass carbon, microbial biomass nitrogen and microbial biomass phosphorus increased by 22.8%, 19.5%, 27.4%, 31.8%, 11.4% and 9.8% than non-rhizosphere soil, respectively.(2)The comparisons of alpha diversity of fungus communities in winter rapeseed decreased significantly, and the abundance of some pathogenic fungus such as Basidiomycetes, Mortispora and Chytridomycetes also decreased significantly. (3) There were significant differences in rhizosphere soil microbial community composition among different types of winter rapeseed. Ascomycetes were the dominant microorganisms in Brassica rape, accounting for more than 83% of the total abundance, followed by Basidiomycetes, Mortieromycetes, Chytridomycetes and Mucoromycota. The dominant microorganisms of Brassica napus were Ochrochytridia and Fungi_phy_Incertae_sedis. (4) The pH, available phosphorus, total phosphorus, alkali-hydrolyzed nitrogen, total nitrogen, organic carbon and soil water content were important environmental factors affecting the composition of soil fungal communities. (5) The activity of phosphatase and urease in Brassica rape was higher than that in Brassica napus, but catalase is the opposite. (6) The amount of microorganisms and soil enzymes significantly altered soil physicochemical properties,such as AN, AP, TP were significantly increased and soil salinity was reduced,and the Brassica rape was more significant than the Brassica napus. In conclusion, planting winter rapeseed can improve soil fertility and soil physicochemical properties by changing the composition and structure of rhizosphere soil fungal community, thereby driving the increase of soil enzyme activity, the content of soil available nitrogen and phosphorus, and adjust pH, thus having good ecological benefits. The results provided theoretical reference for the study of winter rapeseed-soil-microbial interaction and the screening and separation of probiotics, and provided certain support for further expanding the planting area of winter cover crops and optimizing the agricultural industrial structure.