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Microporous Cu-Zn were prepared by powder metallurgy, which were then employed as precursors to prepare micro-/nano-porous coppers by dealloying. Firstly, the effect of sintering temperature on the microstructures of Cu-Zn precursors was investigated. Then, the phase constitution and microstructures of Cu-Zn alloys after dealloying in HCl solutions with different concentration were compared. Finally, the electrochemical behavior of Cu-Zn precursors during dealloying process was analyzed. The results showed that micro-/nano-porous coppers can be prepared by powder metallurgy and dealloying. Different sintering temperature contributed to the variation of phase content and porous structure of Cu-Zn precursors, which then caused significant differences during delloying process. Cu₃₀Zn₇₀ precursors consisted of Cu₅Zn₈ and CuZn₅, and CuZn₅ was corroded preferentially during dealloying process. While Cu₅₀Zn₅₀ precursors consisting of single phase CuZn showed a much slower corrosion rate. Both precursors were dealloyed incompletely in 0.1mol/L HCl solution. When the concentration of HCl solution was increased to 0.5mol/L, Zn was completely dealloyed from both precursors and nanoporous structures were formed in micro-scale ligaments. The diameters of micro pores and nano pores were about 3.02~3.68μm and 157~ 183nm, respectively.