CdS-loaded K4Nb6O17 composite photocatalysts (designated CdS@K4Nb6O17) were prepared via a reverse microemulsion method. The CdS particles scattered on the surface of K4Nb6O17 displayed a relatively uniform size distribution around 50 nm. The absorption edge of K4Nb6O17 was shifted to the visible light region after CdS loading, and the recombination of photo-generated electrons and holes was suppressed after CdS deposition. The CdS(20 wt.%)@K4Nb6O17 composite contained an optimal loading and possessed the highest photocatalytic activity observed, degrading approximately 90% of RhB after 120 min under visible light irradiation. The composite photocatalysts were found to be fairly photostable through recyclability experiments. The mechanism of separation of the photogenerated electrons and holes at the CdS@K4Nb6O17 photocatalyst was discussed. (C) 2013 Elsevier B.V. All rights reserved.