Synergistic　effect　of　atmospheric　non-thermal　plasma　generated　by　dielectric　barrier　discharge　and　nano　titania　photocatalyst　for　benzene　decomposition　was　tested.　The　paper　indicated　the　effect　of　photocatalyst　on　removal　efficiency　of　benzene,　the　compare　of　photocatalyst　characteristic　in　different　high　temperatures　by　heat　treatment,　analysis　of　by-products.　The　results　showed　that　the　effect　of　degradation　was　visible　by　added　photocatalyst　in　the　plasma　reactor.　When　concentration　of　benzene　was　600　mg/m(3)　and　electric　field　strength　was　10　kV/cm,　the　removal　efficiency　of　benzene　was　increased　up　to　81　%　without　photocatalyst.　At　the　same　condition,　the　removal　efficiency　was　increased　to　15　%　higher　with　photocatalyst.　Nano　titania　crystal　wits　anatase　crystal　in　450　degrees　C　heat　treatment　which　is　best　for　benzene　removal.　The　plasma　reactor　packed　with　photocatalyst　shows　a　better　selectivity　of　carbon　dioxide　than　that　without　photocatalyst.　By-products　are　mostly　carbon　dioxide,　water　and　a　small　quantity　of　carbon　monoxide.