The invention discloses an infrared image correction method based on the single image grey-scale characteristic. By aiming at an infrared image in a typical macroscopic uneven mode, a round mean value characteristic curve concept is proposed to describe the uneven mode of the infrared image, and an uneven image is corrected by the curve. The infrared image correction method comprises the following steps: firstly, analyzing the round mean value characteristic curve of the black body image of a typical infrared image to obtain the distribution characteristic of the unevenness; secondly, carrying out filtering processing to the round mean value characteristic curve of the infrared image to be corrected so as to reduce the interference due to noise and scenes; thirdly, fitting the filtered round mean value characteristic curve on the basis of the distribution characteristic; and finally, carrying out unevenness correction to the infrared image to be corrected by a fitted curve. Because the unevenness characteristic of the infrared image can be better given by the round mean value characteristic curve, the better correction effect can be obtained with the method.