An object detection method and apparatus is provided. When an object pixel having a target pixel value is found while an image including an object is scanned at intervals of a preset number of pixels, whether or not each pixel around the object pixel has the target pixel value is sequentially determined, while spreading to pixels around the object pixel, to find an entire pixel region constituting the object and position values of the found pixels are stored. This ensures that an entire pixel region of the object is simply, easily, quickly, and correctly found.