A simple one-step procedure for 1D structures: Directed self-assembly of hybrid materials based on a poly(propyleneimine) dendrimer template and CdSe nanoparticles in situ is an effective nanofabrication tool to form well-defined semiconducting hybrid nanofibers coated with discrete Au nanoparticles (nanoalloy). Such functional nanofibers will offer great potential in various applications, such as biological markers and nanoprobes among others.