A method and an electronic apparatus for wave detection are provided. The method is adapted to the electronic apparatus having an image capturing device and a processor, and includes following steps: successively capturing a plurality of images; calculating a difference image between each two adjacent images among the images, and determining whether a variation degree of the difference images is over a predetermined degree according to pixel values of a plurality of pixels in the difference images; if the variation degree is over the predetermined degree, detecting a variation range formed by the pixels having the pixels values to which a predetermined variation is occurred in each of the difference images and determining whether a variation frequency of the pixel values within the detected variation range is over a predetermined frequency; and if the variation frequency is over the predetermined frequency, determining that a wave movement appears in the images.