A\} new highly ordered mesostructured silica(possible space group \%Fm3m\%) was synthesized by \{using\} tri\|headgroup quaternary ammonium surfactant \{CH\-3(CH\-2)\-\{17\}N\++(CH\-3)\-2CH\-2CH\-2N\++(CH\-3)\-2CH\-2CH\-2\}CH\-2N\++(CH\-3)\-3\53Br\+-(C\-\{18\|2\|3\|1\}) under a basic condition. The cubic mesoporous silica product has an \{average\} pore size of 2.9 nm, a large BET specific surface area of 991 m\+2/g and a large pore volume of \{0.98 cm\+3/g\}.