Ten　kinds　of　activated　carbon　from　different　raw　materials　were　used　as　supports　to　prepare　ruthenium　catalysts.　N-2　physisorption　and　CO　chemisorption　were　carried　out　to　investigate　the　pore　size　distribution.　and　the　ruthenium　dispersion　of　the　catalysts.　It　was　found　that　the　Ru　dispersion　of.　the-catalyst　was　closely　related　to　not　only　the　texture　of　carbon　support　but　also　the　purity　of　activated　carbon.　The　activities　of　a　series　of　the　carbon-supported　barium-promoted　Ru　catalysts　for　ammonia　synthesis　were　measured　at　425　degreesC,　10.　0　MPa　and　10　000　h(-1).　The　result　shows　that　the　same　raw　material　activated　carbon,with　a　high　purity,　high　surface　area,　large　pore　volume　and　reasonable　pore　size　distribution　might　disperse　ruthenium　and　promoter　sufficiently,　which　activated　carbon　as　support,　could　be　used　to　manufacture　ruthenium　catalyst　with　a　high　activity　for　ammonia　synthesis.,The　different　raw　material　activated　carbon　as　the　support　would　greatly　influence　the　catalytic　properties　of　the　ruthenium　catalyst　for　ammonia　synthesis.　For　example,　with　coconut　shell　carbon　(AC1)　as　the　support,　the　ammonia　concentration　in　the　effluent　was　13.170%　over　4%Ru-BaO/AC1　catalyst,　while　with　the　desulfurized　coal　carbon(AC10)　as　the　support,　that　in　the　effluent　was　only　1.　37%　over　4%　Ru-BaO/AC10　catalyst.