Abstract Internal friction peaks in two types of pure silver and six types of silver alloys were investigated with a torsion pendulum of about 1 cps. Comparisons were made on the variations of internal friction of both single and polycrystalline specimens of different compositions before and after different degrees of internal oxidation.Experimental results show: (1) The peak temperature of high purity silver (99.99%) appeared at about 130℃ when internal friction was measured in air in the course of heating, but the peak disappeared when measurements were taken in a reverse course (i.e. during cooling) from a temperature of ～400℃ or above. (2) To all specimens of lower purity (99.95 % Ag) and the three types of silver alloys, two peaks, one at 130°-260℃ and another at 380-430℃, have been observed in the course of heating. The height and the position (temperature) of both peaks depend on the concentration of impurities. When measurements were taken in the course of cooling, the low temperature peak, resembling that in high purity specimens, also disappeared; but the high temperature peak remained unaffected. The effect of alloy elements seems to give rise to the high temperature peak, and simultaneously to suppress the occurence of the low temperature peak. At Al concentrations in excess of 0.05% (0.2 at. %) only the high temperature peak was observed. (3) After internal oxidation treatments the peak heights of alloy specimens decreased with increasing time of treatment.