We report a general and green approach to synthesize monodisperse ceria hollow spheres with tunable shell structure. After ceria precursor is coated on monodisperse poly(styrene-co-acrylic acid) spheres via a sol–gel method, ceria hollow spheres are successfully fabricated by calcination. The as-obtained hollow spheres exhibit enhanced photocatalytic activity under visible light. Our present work could not only provide a useful direction for the scale-up fabrication of other metallic oxide hollow spheres with tunable shell structure, but also open a new doorway to ceria based photocatalyst synthesis in an aqueous phase.