Ceria nanoparticles (average secondary particle size: 80 nm) in an aqueous suspension were successfully extracted to the toluene phase by using surfactants as the extracting agent. AOT (Aerosol (R) OT: diisooctyl sodium sulfosuccinate) and AOT mixed with SPAN65 (SPAN (R) 65: sorbitan tristearate) were found to be effective in extracting ceria nanoparticles. Addition of SPAN65 markedly enhanced the extracting capability. The ceria nanoparticles recovered using the mixed surfactant were successfully redispersed in polymethylmetacrylate (PMMA) with optical transparency retained. Addition of SPAN65 is considered to increase the spontaneous curvature radius of the surfactant layer to surround the ceria nanoparticles successfully.