Nanoscale heterostructures with modulated composition and/or passivated interfaces can enrich/enhance the performance of diverse compact devices. Here, we report the synthesis of nanoscale pearl-like InP nanowire heterostructures wrapped with InP quantum dots (QDs)-decorated PxOy nanospheres periodically along the length by a chemical vapor deposition (CVD) method. Compared with the Raman modes of bulk InP, additional surface phonon (SP) peak, which results from InP QDs finite size, is observed in these pearl-like heterostructures. Room-temperature photoluminescence (PL) showed that these pearl-like heterostructures simultaneously exhibited two broad emission bands at 768 and 846 nm, which belong to the PL emission of InP QDs and InP trunks, respectively. The significant blue shift of the two emission bands compared with the intrinsic luminescence of InP crystal at 920 nm is attributed to the quantum confinement effects. A self-organization model is proposed to illustrate the formation of the heterostructures. These interesting pearl-like InP/PxOy heterostructures may find potential applications in constructing new nanoscale optoelectronic devices.