A fingerprint identifying system includes a finger press plate, an image-capturing unit, a light-diffusion member, at least one microstructure layer, and a light source. The light-diffusion member is disposed below the finger press plate and above the image-capturing unit, and has a through hole in alignment with the image-capturing unit. The microstructure layer is disposed on the light-diffusion member. The light source is disposed below the light-diffusion member and around the image-capturing unit.