Abstract: Antagonistic effect of five species of Pleurotus, including P. ostreatus, P. sajor-caju, P. cornucopiae, P. florida and P. eryngii on second stage juveniles (J2) of Meloidogyne javanica were studied, in vitro. On water agar, all of the species tested produced tiny droplets of toxin. Nematodes touching such droplets showed a sudden response and became colonized by the fungi after 24-48 h. Filtrates of the tested fungi grown in malt extract broth were toxic on the nematodes but this toxicity varied between species. Culture filtrates of P. ostreatus showed the highest nematicidal activity toward M. javanica J2 and the lowest toxic effect was observed in filtrates of P. eryngii. A linear relationship was proved between increasing toxin concentration and the percentage of dead nematodes.