The present invention discloses a method of filming a high dynamic range video. The method includes: using an image sensor to capture an original frame which is interlaced by a plurality of long exposure areas and a plurality of short exposure areas; forming a long exposure field via a plurality of long exposure areas and forming a short exposure field via a plurality of short exposure areas; forming a reconstructed long exposure field and a reconstructed short exposure field having the same resolution as the original frame via a reconstruction process by a pixel value of each pixel in the long exposure field and the short exposure field; and forming a high dynamic range image based on the pixel value of each pixel of the reconstructed long exposure field and the reconstructed short exposure field via a merging process.