A series of beta-Bi2O3/BiOClheterojunction photocatalysts were successfully synthesized by in-situ treatment of beta-Bi2O3 with HCl. Compared to pure beta-Bi2O3, the as-synthesized beta-Bi2O3/BiOCl composites displayed unexpectedly high visible-light photocatalytic activity for RhB degradation, which was even higher than that of P25 under UV light. Based on the results of transient photocurrent measurement and trapping experiments of active species, the enhanced photocatalytic activity could be ascribed to the formation of heterostructure between beta-Bi2O3 and BiOCl, leading to the efficient separation of electron-hole pairs. This research may establish foundation for practical application of the new visible-light-active beta-Bi2O3-based heterojunction photocatalysts.