This invention discloses a digital zooming apparatus for adjusting the size of a sensed image sensed by a sensor. The digital zooming apparatus includes an adjusting module, a first image-processing module, a storage module and a second image-processing module. The adjusting module connected to the sensor receives the sensed image and adjusts the sensed image according to a zooming factor to produce an adjusted image. The first image-processing module connected to the adjusting module processes the adjusted image according to a first predetermined condition and a second predetermined condition to produce a first image. The storage module connected to the first image-processing module stores the first image. The second image-processing module connected to the storage module receives the first image and processes the first image according to the second predetermined condition to produce a second image.