The invention discloses an anti-noise method for detecting the damage of a beam structure through employing a vibration mode, and the method comprises the steps: firstly introducing a modulation parameter into a Gaussian function, solving the second derivative of the Gaussian function, and obtaining a function for recognizing the damage of the beam structure; secondly obtaining a function suitable for the recognition of the damage of the beam structure in a noise environment through introducing a scale parameter into the function; thirdly carrying out the convolution of a vibration mode signal of the beam structure and the anti-noise damage recognition function, and gradually increasing the scale parameter till noise interference disappears if the convolution result has the noise interference; finally judging whether there is damage of the beam structure or not according to a condition whether there is a peak value in the convolution result, and determining the position of the damage according to the position of the peak value. The method integrates two functions: noise reduction and damage feature recognition, can accurately judge the local damage of the beam structure under the interference of environment noise, and detects the position of the damage.