Disclosed are an apparatus and a method for extracting an edge to be used for extracting a feature point of an object in an image. The present invention proposes an image edge extracting apparatus and method that remove noise in an input image, calculate a gradient of an image in a noise-removed image, measure magnitude of the gradient, extract an edge having a maximum thickness value, and then calculate a threshold using a ratio of the extracted edge, and detect a final edge robust against noise based on the threshold.