Recent results on molecular-beam epitaxy growth of the quantum dot InGaAs/GaAs heterostructures for long-wavelength lasers-on GaAs substrates are presented. As a result of optimization of the growth procedure for active region and emitter layers low-threshold current density (45-80 A/cm(2)) long-wavelength (1.27-1.3 mum) laser diodes may be fabricated with high reproducibility.