Abstract: Data on the growth and physical properties of nanostructures of the type “InAsP insert embedded in InP nanowire (NW)” grown on Si (111) surfaces by Au-assisted molecular-beam epitaxy are presented. It is found that nearly 100%-coherent NWs can be grown with a widely varying surface density. A relationship between the optical and structural properties of the NWs is revealed. It is shown that the NWs under study are formed of a purely wurtzite phase. The suggested technology opens up new opportunities for the integration of direct-gap III–V materials and silicon.