Carbon black (CB) nanoparticles were encapsulated by poly(vinyl alcohol) (PVA) by a simple method of coacervation. Transmission electron microscopy (TEM) images clearly demonstrated that the successful encapsulation of PVA happened at the surfaces of CB nanoparticles. The particle-size distribution measurements indicated that the diameters of the obtained PVA-encapsulated CB (CB@PVA) nanoparticles were distributed within the nanoscale dimension. This strategy avoids the complicated polymerization process involved in the counterpart of polymer-coating approaches.