A bioassay procedure was developed to assess the toxicity of Bacillus thuringiensis crystal protein against Meloidogyne hapla, a root-knot nematode, under laboratory conditions. Reproducibility and precision of the bioassay results were optimal when forty 2nd stage juveniles were incubated in the dissolved crystal pro- tein solution at 25℃, pH9.0 for 7 days. The juveniles were stained with 1% KMnO4 for 2 hours or methylene blue solution for 1 hour to distinguish riving and dead ones. By the bioassay procedure, the LC50 value of strain YBT-1532 crystal protein against M. Hapla was determined as 0.304±0.086 mg/mL ( LC50±1.96SE). Moreover, the strain YBT-1532 showed toxicity to Caenorhabditis elegans, a free-living nematode. All results indicated that YBT-1532 is a toxic strain to plant-parasitic nematode, and has the potential to control plant- parasitic nematode.