A heat-assisted magnetic recording head (HAMR) head includes a magnetic recording head including a recording pole for applying a magnetic recording field on a magnetic recording medium and a return pole magnetically connected to the recording pole to form a magnetic path, a light source for emitting light, and an optical transmission module including an photonic crystal waveguide disposed at a side of the magnetic recording head to guide light incident from the light source and a nano aperture for enhancing an optical field by varying an intensity distribution of the light guided through the photonic crystal waveguide.