Abstract: The changes of microstructure, mechanical and damping properties of Fe-17Mn-8Cr alloy during multi-directional forging process were investigated by tensile testing and dynamic thermal mechanical analyzer. The results show that during multi-directional forging process the ε-martensite and γ-austenite plates were greatly refined and more uniformly distributed. Meanwhile, a high density of dislocations was introduced and yield strength was improved obviously. The logarithmic decrement of Fe-17Mn-8Cr alloy after multi-directional forging declined but the alloy still had a high damping capacity. The damping mechanism of this alloy was interaction between the effect of variant crossing degree of ε-martensite on γ/ε interface movement and the effect of high density of dislocations on stacking fault movement.