The three fungal fermentation liquid of ZB-4，ZW-3 and XX-8 were used in treating vegetable root-knot nematodes vitro bioassay and in the greenhouse pot experiment.The results showed that: in 24,48,72 hours treatment,all the fermentation liquid of ZB-4，ZW-3 and XX-8 have certain inhibitory effect on root-knot nematodes at different dilution ratios.In 72 hours treatment,the 2 times dilution of the three fungi strains fermentation liquid broth showed the rectified inhibiting efficiencies to J2 as 95.27%,91.27% and 86.58% respectively.The rectified inhibiting efficiencies to J2 of 4 times dilution were 68.52%,84.05% and 60.33% in 72 hours.In greenhouse pot experiment,the 2 times broth of three fungi were used to treat tomato seedlings. After 45 days,compared to the control, the reducing rate of nematodes were up to 46.7%, 43.3% and 36.7% respectively.The controlling efficiencies reached 23.81%,19.52% and 35.71% respectively.Furthermore,our investigation in 22 days and 45 days showed that the 2 times broth could promote the growth of tomatoes. 