Abstract: To investigate the effects of corn rotation combined with straw mulching on the rhizosphere soil of long-term continuous potato cultivation, the rhizosphere soil of potatoes that had been continuously planted for 8 years was used as the object of study. Four treatments were set up: no treatment (CK), corn straw mulching (T1), corn rotation combined with corn straw mulching (T2), and corn rotation (T3). High-throughput sequencing, soil physical and chemical analysis, and multivariate statistical processing methods were used to compare and study the effects of the four treatments on the composition and structure of the soil fungal community, dominant groups, diversity, and related physical and chemical indicators in the rhizosphere of potatoes. The results showed that compared with CK, T1, T2, and T3 treatments reduced the richness of soil fungi in the rhizosphere of potatoes but increased the diversity of soil fungi in the rhizosphere of potatoes. The Shannon index was the highest in the T2 treatment. The results of PCoA and cluster analysis based on soil fungal composition showed that the soils of the four treatments could be divided into two categories: CK-T1 and T2-T3. The dominant phyla of soil fungi in the rhizosphere of potatoes were Ascomycota, Basidiomycota, Mortierellomycota, and Chytridiomycota. The effects of different treatments on fungal phyla were significantly different: compared with CK, the proportion of Ascomycota decreased in T1 and T3, slightly increased in T2, the proportion of Mortierellomycota generally increased, the proportion of Chytridiomycota increased sharply in T2/T3, and the proportion of Basidiomycota increased in T1 and decreased in T2/T3. Corn rotation alone significantly changed the composition and structure of the soil fungal community in the rhizosphere of potatoes and increased the proportion of the beneficial phylum Mortierellomycota in the soil. The results of environmental factor correlation analysis indicated that soil available nitrogen and soil urease were the main environmental factors affecting the rhizosphere soil fungal community. The T2 and T3 treatments improved the soil microenvironment and reduced the proportion of the harmful genus Plectosphaerella by 48.1% and 45.0%, respectively. The study demonstrated that corn rotation combined with straw mulching could significantly increase soil organic matter, help alleviate the spread and occurrence of potato diseases, improve its quality and yield, and effectively alleviate the occurrence of soil-borne diseases.