The fungus Pochonia chlamydosporia is one of the most promising biocontrol agents for some most important nematodes.It is easily cultivated in vitro and produces chlamydospores, which are resistant resting spores, which prolong their survival in the field and in storage.To improve the yield of chlamydospores,a two-stage cultivation method was used to determine nutritional and environmental conditions affecting chlamydospore production of P.chlamydosporia strain PC152.The results showed that soluble starch and NaNO3 were the optimum carbon source and nitrogen source for chlamydospore production;the optimum C ∶ N ration was 2.5 ∶ 1.The combination of carbon source and nitrogen source were soluble starch/NaNO3 and sucrose/NaNO3;weak basic (alkaline) medium (pH =8.0) was beneficial to chlamydospore production.NaC1 at 1.00% (W/V) in the medium induced chlamydospore production.