Ultrafine dispersed copper powders were prepared from copper (I) oxide (Cu2O) slurry by a wet chemical reduction with hydrazine as a reductant. Palladium chloride (PdCl2) was used as a nucleator along with its polymer stabilizer, polyvinylpyrrolidone (PVP). Sodium pyrophosphate (Na4O7P2) was added as a surfactant. It was found that the use of Cu2O and Na4O7P2 exhibit very strong impact on dispersity of the prepared Cu powders. In this study, we indicate the critical conditions at which the particles aggregation still occurs even though the powders produced at high zeta potential resulted from an appropriate addition of Na4O7P2.