Abstract: The effect of ball milling time on the particle size distribution and powder morphology of the fine copper powders prepared by high energy ball milling was studied in this paper. The results show that, when the ball milling time is less than 20 h, the particle size distribution index (D₃₀, D₅₀, and D₉₀) of the copper powders declines with the increase of ball milling time, and the agglomeration of copper powders is not obvious. After the ball milling time exceeds 20 h, with the increase of milling time, the agglomeration of copper powders is obvious, and the uniformity of copper powders is decreased. When the milling time is 20 h, the particle size distribution, phase composition, and powder morphology of the copper powders show the best. At this time, the uniformity of copper powders is improved, the powder surface is relatively flat, the particle size distribution distance reaches the minimum value (D_δ=1.723), the specific surface area is 0.796 m²·g^‒1, and the median diameter (D₅₀) is 9.97 μm.