Abstract: Foamed Zn-Al eutectoid alloys with macroscopic pores were prepared by air pressure infiltration process. The internal friction and relative dynamic modulus were tested on a multifunction internal friction apparatus (MFIFA) at low frequencies, low strain amplitude and over a temperature range of 25 to 400 ℃. The effects of macroscopic pores on the damping behavior of the alloy were studied. The results show that the damping capacity of the Zn-Al alloy was enhanced by introducing of the macroscopic pores which increased by 2-4 times in comparison with dense Zn-Al alloy. The damping capacity increased with decreasing the macroscopic pore size, increasing the porosity, decreasing the frequency and increasing the strain amplitude.