Chaos characteristics of the Holmes Duffing equation are described, and the mechanism of its application on detecting a weak signal from strong background noise is elaborated. As for the problem of identifying structural damage in a strong noise environment, a damage location method based on the Holmes Duffing equation and the response sensitivity method is proposed. A set of specific parameters is selected for the extraction of a response signal, thus avoiding the cumbersome process of the traditional Duffing oscillator parameters selection. A higher noise level is also considered, and the noise calculation result is less under the same noise level. This method is applied to the three-dimensional structure model, and the results show that this method can effectively detect the location of structural damage under strong background noise, which can provide a better methodology for structural damage identification.