AlGaAs nanowires with InAs quantum dots on the silicon surface were synthesized by molecular-beam epitaxy. Morphological and optical properties of grown nanostructures were studied. It is important to note, that emission from  quantum dots is observed in the wavelength range from 780 to 970 nm. Assumptions about the nature of short-wave radiation from quantum dots were formulated. In particular, one of the reasons may be the significant desorption of indium atoms and the presence of gallium atoms in the catalyst droplets during growth at the substrate temperature of 510 °C. Our work, therefore, opens new prospects for integration of direct bandgap semiconductors with silicon  platform.