Spherical Bi2MoO6 nanoarchitectures with scale of 500 nm–2 μm were prepared by a solvothermal reaction using bismuth nitrate and ammonium molybdate as precursors. Ag3PO4 nanoparticles were then deposited onto the surface of Bi2MoO6via a facile deposition–precipitation technique. The photocatalytic tests display that the Ag3PO4/Bi2MoO6 nanocomposites possess a much higher rate for degradation of rhodamine B and methylene blue than the pure Ag3PO4 nanoparticles and Bi2MoO6 under visible light. The catalytic activity of the composite photocatalysts is greatly influenced by the loading level of Ag3PO4. The 50 mol% Ag3PO4-loaded Bi2MoO6 spheres exhibit the highest photocatalytic activity in both the decolorization of RhB and MB. The observed improvement in photocatalytic activity is associated with the extended absorption in the visible light region resulting from the Ag3PO4 nanoparticles, and the effective separation of photogenerated carriers at the Ag3PO4/Bi2MoO6 interfaces. In addition, the composite can be easily reclaimed by sedimentation without any loss of its stability. Moreover, the tests of radical scavengers confirmed that h+ and ˙OH were the main reactive species for the degradation of RhB.