ZnO nanorods were prepared on ITO substrate using the hydrothermal method and then CdS quantum dots were synthesized on the ZnO nanorods with the chemical bath deposition method. The morphologies and crystalline structure of the as-prepared samples were characterized by SEM and XRD, respectively. The results indicated that after the chemical bath deposition, spherical CdS quantum dots were evenly coated on the surface of ZnO nanorods with good crystalline quality. The photodetectors made up of ZnO nanorods and ZnO nanorods/CdS quantum dots showed good response under ultraviolet(UV) irradiation. The photocurrent of ZnO nanorods/CdS quantum dots detector(052 mA) was 7 times higher than that of ZnO nanorods. In addition, the photodetector based on ZnO nanorods/CdS quantum dots exhibited good response to green and blue light.