Root-associated endophytic fungi (RAF) are found asymptomatically in almost all plant groups. However, little is known about the compositionspotential functions of RAF communities associated with most Orchidaceae species. In this study, the diversity of RAF was examined in four wild epiphytic orchids, Acampe rigida, Doritis pulcherrima, Renanthera coccinea,Robiquetia succisa, that occur in southern China. A culture-independent method involving Illumina amplicon sequencing,an in vitro culture method, were used to identify culturable fungi. The RAF community diversity differed among the orchid roots,some fungal taxa were clearly concentrated in a certain orchid species, with more OTUs being detected. By investigating mycorrhizal associations, the results showed that 28 (about 0.8%) of the 3527 operational taxonomic units (OTUs) could be assigned as OMF, while the OTUs of non-mycorrhizal fungal were about 99.2%. Among the OMFs, Ceratobasidiaceae OTUs were the most abundant with different richness, followed by Thelephoraceae. In addition, five Ceratobasidium sp. strains were isolated from D. pulcherrima, R. succisa,R. coccinea roots with high separation rates. These culturable Ceratobasidium strains will provide materials for host orchid conservationfor studying the mechanisms underlying mycorrhizal symbiosis.