Abstract: One hundred and fifty two soil root samples were collected from 28 counties of root-knot nematodes disease areas of Yunnan Province. Four hundred fungal antagonists respectively associated with egg masses,eggs,sedentary females and vermiform nematodes of tobacco root-knot nematodes were isolated by direct method and baitting method.These fungal antagonists were identified down to twenty one genera,they are Paecilomyces,Fusarium,Penicillium,Trichoderma,Verticillium,Aspergillus,Phoma,Pochonia.Harposporium,Mucor,Geotrichum,Doratomyces,Sarcinella,Alternaria,Gliomastix,Cladosporium,Chaetomium,Cylindrocarpon,Monacrosporium,Arthrobotrys,Cephaeosporium,and some sterile fungi.The isolation frequency of Paecilomyces lilacinus,Fusarium oxysporum and Pochonia chlamydospora took up above 60%.The results showed that the fungal antagonists of tobacco root-knot nematodes have abundant biodiversity,the species and amount of fungal antagonists in the egg masses, eggs and sedentary females were higher than that of vermiform nematodes,and the species and the amount of different samples were distinctly different.The fungal biodiversity could supply abundant biocontrol resource for root-knot nematodes.