Root-knot nematode, Meloidogyne incognita is the most economically important plant parasitic nematode species that cause serious damage to most agricultural crops including tomato worldwide. Nematicides do not provide long-term suppression of root-knot nematodes, and environmental and human health concerns are resulting in increased restrictions on their use. A greenhouse experiment was conducted to evaluate the effect of silver nanoparticles (AgNPs) at concentrations of 0.25, 0.5 and 1 mM as a potential nematicide on M. incognita infecting tomato. AgNP was biologically and chemically synthesized by a reaction of silver nitrate with ginger (Zingiber officinale) rhizomes aqueous extract and sodium borohydride, respectively. Results indicated that application of AgNPs improved plant growth and reduced nematode infection in comparison to silver nitrate and control treatments. The highest increment of fresh weight as well as the lowest numbers of galls and egg-masses was obtained when tomato plants was treated with AgNP produced by ginger extract at 1 mM.