Abstract: Nanometer copper powder and nanometer copper colloid were prepared by liquid phase reduction method, CTAB and PVP were used as dispersants. The nanometer copper powders were characterized by X-ray diffraction and SEM, and the stability of nanometer copper colloid was tested by gravity sedimentation. The results show that the liquid-phase reduction method can produce nanometer copper powders with high purity. When the concentration of CTAB is 0.12 mol/L, the average particle size of copper powders is the smallest, 20 nm. When the concentration of CTAB is 0.14 mol/L and the ultrasonic duration is 20 min, the stability of the nanometer copper colloid is the highest. When the concentration of PVP is 6×10^-4 mol/L, the stability of the average particle size of copper powders is the smallest, 20 nm. When the concentration of PVP is 7×10^-4 mol/L and the ultrasonic dispersion duration is 20 min, the stability of the nanometer copper colloid is the highest.