The present invention is to provide a method for achieving a clear and precise optical zooming mechanism, which is applied to an electronic device equipped with a wide-angle image capturing element and a long-focus image capturing element. The wide-angle image capturing element and the long-focus image capturing element are controlled by the electronic device for capturing a wide-angle image and a long-focus image of a same spot simultaneously and respectively. The method enables the electronic device to sequentially perform an exposure and white balance adjustment process, a robust image matching algorithm and an image morphing fusion process to the wide-angle image and the long-focus image, respectively, so as to generate a clear and precise optical zooming image of the spot without having a significant skipping phenomenon occurred in an object within two zooming images.