The authors demonstrated enhanced efficiency of poly[2-methoxy-5-(2-ethylhexyloxy-pphenylenevinylene)]/ZnO nanorods hybrid solar cells sensitized by CdS quantum dots (QDs) prepared by a chemical bath deposition method. A thin ZnO film was adopted to well control the length of the ZnO nanorods and act as a hole blocking layer. An appropriate coating of the CdS QDs on the ZnO nanorods leads to a maximum power conversion efficiency of 0.65%, which was increased 6.5 times compared with the one without using QDs. The dramatically improved efficiency is attributed to the cascade structure formed by the CdS QDs coating, which results in enhanced open-circuit voltage, exciton dissociation efficiency, and charge carriers extraction efficiency. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3598171] All rights reserved.