A novel and precise ionic self-assembly (ISA) construction strategy for the self-assembly of polymeric quaternary ammonium salts (polyionene) and Anderson-type polyoxometalate (beta-Mo8O264-) to form a three-dimensional nanoflower structure was developed successfully and used for oxidative desulfurization (ODS) of fuels for the first time. Furthermore, the morphologies of the self-assembled structures could be precisely regulated by varying the reaction conditions, including the concentrations of the polyionene and temperature. Additionally, nitrogen sorption analysis indicated the porosity with a surface area up to 140 m(2) g(-1). Remarkably, the nanoflowers showed excellent conversion (98.9%) toward the ODS process with six times of recycling. This could be ascribed to the large amount of active sites dispersed over the relatively high specific area, providing contact with reactants in the ODS process. This facile and innovative fabrication method shed new light on the versatile design and construction of nanostructures.