We have studied magnetization reversal behaviors of diamond-shaped NiFe nanofilm elements with different length-to-width ratios (LWRs) between long and short diagonals by micromagnetic simulation. The results show that the reversal process of the diamond-shaped element strongly depends on the LWR. If the LWR is smaller than 2, the reversal starts at the element edge, but it starts from the center of the element with larger LWR. With a bias field and when the LWR is larger than 2, all the elements experience a similar reversal process, which is simple and unique. In addition, the switching field becomes stable and nearly constant. These results suggest that the diamond-shaped NiFe nanofilm element can be potentially used in magnetic random access memory.