Damage-induced changes in natural frequencies, damping ratios and mode shapes can be detected using Experimental modal analysis (EMA). And it uses differences of measured modal properties from baseline or nominal values to identify the location and severity of damage. But the large amount data and complex information can lead to wrong judgment. A kind of multi-information fusion method was applied in damage detection system based on Dempster-Shafer evidence theory. The constructed integrated parameter performed well in the sensitivity and reliability compared to conventional single parameter methods. And the result showed that the multi-information fusion method can be widely used in damage diagnosis.