Zero-valent iron (ZVI) nanoparticles are prepared by wet chemical method, unlike conventional methods, we applied a water-soluble dextrin、CMC and starch in the preparation. The starch serves as a stabilizer and dispersant that prevents the resultant nanoparticles from agglomeration, and characterized by XRD、SEM and USP. Compare the dispersion of particles and particle size in progress of reducing. According to the characterization results, the nanoparticles can be dispersed more efficiently, maintained the activity of it owned and kept the stability longer with the dispersing agent. Based on the results obtained, the starch as a dispersion agent on the preparation of Zero-valent iron (ZVI) nanoparticles is an ideal approach.