In　this　paper　the　inactivation　efficiency　of　TiO2　on　H1N1　influenza　virus　under　365　nm　UV　illuminations　was　reported.　Hemagglutination　tests　were　used　to　determine　the　change　of　the　titer　of　H1N1　and　TEM　were　used　to　observe　the　deformation　of　H1N1　during　photocatalysis.　TiO2　photocatalysts　were　prepared　by　a　modified　sol-gel　method　and　characterized　by　XRD,　BET　and　Zeta　potential　measurements.　The　dependence　of　inactivation　efficiency　on　dosage,　calcinations　temperature　and　surface　charge　state　of　the　photocatalysts　was　investigated.　The　results　show　that　TiO2　calcinated　at　400　degrees　C　had　the　best　performance　and　the　surface　charge　state　of　the　photocatalysts　could　influence　the　inactivation　efficiency　significantly.　TEM　micrographs　reveal　that　H1N1　was　attacked　at　its　surface　projections　and　it　could　be　decomposed　and　mineralized　for　a　longer　photocatalytic　treatment.