A thermally assisted magnetic recording head includes a flying slider, a magnetic field generation device mounted on the flying slider, a first waveguide disposed near the magnetic field generation device for guiding incident light from a top surface of the flying slider on a side of the flying slider toward an air bearing bottom surface of the flying slider, an optical near-field generator disposed at an emission end of the first waveguide, a second waveguide which is separate from the first waveguide and which is spaced from and coupled to the first waveguide at a distance of no greater than a light wavelength, and a first optical detector for detecting the intensity of light propagating in the second waveguide. The first waveguide and the second waveguide are disposed so as to extend in a direction substantially perpendicular to the air bearing bottom surface of the flying slider.