In　this　work,　the　positively　or　negatively　charged　anatase　TiO2　nanoparticles　were　synthesized　via　a　low　temperature　precipitation-peptization　process　(LTPPP)　in　the　presence　of　poly(ethyleneimine)　(PEI)　and　poly(sodium4-styrenesulfonate)　(PSS).　X-ray　diffraction　(XRD)　pattern　and　high-resolution　transmission　electron　microscope　(HRTEM)　confirmed　the　anatase　crystalline　phase.　The　charges　of　the　prepared　TiO2,　PEI-TiO2　and　PSS-TiO2　nanoparticles　were　investigated　by　zeta　potentials.　The　results　showed　that　the　zeta　potentials　of　PEI-TiO2　nanoparticles　can　be　tuned　from　+39.47　mV　to　+95.46　mV,　and　that　of　PSS-TiO2　nanoparticles　can　be　adjusted　from　-56.63　mV　to　-119.32　mV.　In　comparison　with　TiO2,　PSS-TiO2　exhibited　dramatic　adsorption　and　degradation　of　dye　molecules,　while　the　PEI　modified　TiO2　nanoparticles　showed　lower　photocatalytic　activity.　The　photocatalytic　performances　of　these　charged　nanoparticles　were　elucidated　by　the　results　of　UV-vis　diffuse　reflectance　spectra　(DRS)　and　the　photoluminescence　(PL)　spectra,　which　indicated　that　the　PSS-TiO2　nanoparticles　showed　a　lower　recombination　rate　of　electron-hole　pairs　than　TiO2　and　PEI-TiO2.