The continuous-wave single-mode operation of edge-emitting diode laser based on dual-sided non-quarterwave Bragg reflection waveguide BRW was demonstrated at room temperature. A low-index core was utilized in the laser. The ridge BRW lasers BRLs exhibited an ultra-narrow twin-beam output. Single longitudinal mode emission with a very small spectral linewidth of 0. 052 nm was measured. The lasing spectra showed a periodic modulation in the envelope with a mode spacing of approximately 3. 3 nm. When the injection current of the BRLs was beyond 300 mA a large mode hopping of the emission wavelength was observed.