The invention relates to a slope displacement automatic monitoring method based on an image SURF feature. The method comprises the steps that sequence images of open-pit mine slope monitoring are acquired by a camera; an SURF algorithm is used to extract interest points of the sequence images; interest point matching is carried out on each image; the displacement of an interest point, which matches an interest point in a previous image, of the current image is monitored in real time; the three-dimensional coordinates of the interest points in the sequence images are converted into absolute coordinate positions of WGS-84 world ground coordinate system slope position points; the slope position point corresponding to each interest point in the current image is compared with the slope position corresponding to the matched interest point in the previous image; and if the actual displacement of the slope position point corresponding to an interest point is beyond a slope displacement threshold, the slope position has the tendency of instability or landslide.