In this study, the phenomenon of light trapping in Si solar cells coated with metal (Au) and dielectric (TiO 2 , SiO 2 ) nanoparticles (NPs) is systematically investigated. In contrast to previous reports, herein it is proposed that the photocurrent enhancement of solar cells should be attributed to the limited antirefl ection ability of the Au NP arrays. In other words, the Au NP arrays might not enhance the absorption of the active layer in cells when no light is refl ected from the air-substrate interface. Therefore, the Au NPs are replaced with dielectric NPs, which possess lower extinction coeffi cients, and then the antirefl ection property of the TiO 2 NP arrays is optimized. A simple, rapid, and cheap solution-based method is used to prepare close-packed TiO 2 NP fi lms on Si solar cells; these devices exhibit a uniform and remarkable increase (ca. 30%) in their photocurrents. To the best of the authors' knowledge, this uniform photocurrent enhancement is greater than those obtained from previously reported metal and dielectric NP-enhanced Si wafer-based solar cells.