Root knot nematodes of Meloidogyne spp. are among the most damaging plant pathogens worldwide. Meloidogyne Species Known of this genus which damage olive trees are sporadically found in wild olives, olive nurseries and established orchards; they generate gall on the roots and delay plant growth. In this study, the impact of nematicide toxins of Aldicarb, Enzon, Oxamyl, and Cadusafos with concentrations of 6 and 8 ppm on olive’s root knot nematode in one-year old olive seedlings, collected from Dezfoul, was studied in a greenhouse. The results of this study showed that Rugby toxin with concentration of 8 ppm (79/24 percent reduction in nematode population) and Enzone toxin with concentration of 8 ppm (50/38 percent reduction in nematode population) had, respectively, the most and least effect in the control of nematode. This experiment was done by inoculation of 5000 eggs and second instar larvae in a completely randomized design with three replications.