An image uniformity compensation method for a projection system, the projection system comprising a projection device, the method comprising: projecting, by the projection device, an original test image corresponding to a test luminance onto a projection surface; when the original test image is projected, performing, by a plurality of color measurement devices (120_1-120_13), measurement on the projection surface to acquire a plurality of original color data corresponding to the plurality of measurement positions; the method being characterized by: acquiring a target value by taking a minimum value from a plurality of color space component values of the plurality of original color data; adjusting the original test image by using uniformity compensation information to generate a test image; projecting, by the projection device, the test image onto the projection surface; when the test image is projected, performing, by the plurality of color measurement devices (120_1-120_13), measurement on the projection surface to acquire a plurality of test color data corresponding to the plurality of measurement positions respectively; determining whether a difference between a maximum value and a minimum value among the plurality of color space components of the plurality of test color data is less than a tolerance threshold; if the difference is not less than the tolerance threshold, the image uniformity compensation method further includes: performing interpolation processing by using the plurality of measurement positions and the plurality of color space components of the test color data to obtain each piece of pixel information of an estimated image, so as to establish the estimated image; generating adjustment coefficient information of each pixel according to a ratio of the target value to a pixel component value of each pixel in the estimated image and a convergence coefficient; updating the uniformity compensation information according to the adjustment coefficient information; and adjusting the original test image by using the updated uniformity compensation information. projecting, by the projection device, an original test image corresponding to a test luminance onto a projection surface; when the original test image is projected, performing, by a plurality of color measurement devices (120_1-120_13), measurement on the projection surface to acquire a plurality of original color data corresponding to the plurality of measurement positions; acquiring a target value by taking a minimum value from a plurality of color space component values of the plurality of original color data; adjusting the original test image by using uniformity compensation information to generate a test image; projecting, by the projection device, the test image onto the projection surface; when the test image is projected, performing, by the plurality of color measurement devices (120_1-120_13), measurement on the projection surface to acquire a plurality of test color data corresponding to the plurality of measurement positions respectively; determining whether a difference between a maximum value and a minimum value among the plurality of color space components of the plurality of test color data is less than a tolerance threshold; if the difference is not less than the tolerance threshold, the image uniformity compensation method further includes: performing interpolation processing by using the plurality of measurement positions and the plurality of color space components of the test color data to obtain each piece of pixel information of an estimated image, so as to establish the estimated image; generating adjustment coefficient information of each pixel according to a ratio of the target value to a pixel component value of each pixel in the estimated image and a convergence coefficient; updating the uniformity compensation information according to the adjustment coefficient information; and adjusting the original test image by using the updated uniformity compensation information. performing interpolation processing by using the plurality of measurement positions and the plurality of color space components of the test color data to obtain each piece of pixel information of an estimated image, so as to establish the estimated image; generating adjustment coefficient information of each pixel according to a ratio of the target value to a pixel component value of each pixel in the estimated image and a convergence coefficient; updating the uniformity compensation information according to the adjustment coefficient information; and adjusting the original test image by using the updated uniformity compensation information.