In pot culture, we evaluated the effects of green manure of wild rocket (Diplotaxis tenuifolia (L.) DC.) on cucumber (Cucumis sativus L.) rhizosphere fungal community composition. Cucumber rhizosphere fungal composition was analyzed by high-throughput amplicon sequencing of fungal ITS regions. Results showed that cucumber seedling rhizosphere fungal community composition was different between the fallow treatment and green manure treatment. However, green manure treatment did not affect the cucumber seedlings fungal community alpha diversity. Compared with the fallow treatment, cucumber grown in green manure of wild rocket had higher relative abundance of phylum Ascomycota but lower relative abundance of phylum Zygomycota. Moreover, green manure of wild rocket decreased operational taxonomic units (OTUs) classified as Pseudallescheria and Kernia spp. but increased OTUs classified as Humicola and Fusarium spp. in cucumber rhizosphere.