Provided is a buried ridge waveguide laser diode that has improved temperature characteristics and can reduce optical loss by a leakage current. The buried ridge waveguide laser diode includes: a ridge region that extends vertically with a constant width and is composed of a selective etching layer and a first compound layer formed of a first conductive type material on a portion of the clad layer; and a p-n-p current blocking layer that has a thickness identical to the depth of the ridge region on the clad layer outside the ridge region and includes a second compound layer formed of a second conductive type material opposite to the first conductive type material. At this time, the current blocking layer includes the first compound layer extending on the second compound layer.