Promoters　are　indispensable　components　of　Ru-based　catalysts　to　promote　N-2　activation　in　ammonia　(NH3)　synthesis.　The　rational　addition　and　regulation　of　promoters　play　a　critical　role　in　affecting　the　NH3　synthesis　rate.　In　this　work,　we　report　a　simple　method　by　altering　the　loading　sequence　of　Ba　and　Ru　species　to　modulate　the　Ru-promoter　interface,　thus　significantly　boosting　the　NH3　synthesis　rate.　The　Ba-Ru/GC　BM　catalyst　via　the　prior　loading　of　Ba　rather　than　Ru　over　graphitic　carbon　(GC)　exhibits　a　high　NH3　synthesis　rate　of　18.7　mmol　gcat　(-1)　h(-1)　at　400(degrees)C　and　1　MPa,　which　is　2.5　times　that　of　the　Ru-Ba/GC　BM　catalyst　via　the　conventional　prior　loading　of　Ru　rather　than　Ba　on　GC.　Our　studies　reveal　that　the　prior　loading　of　Ba　benefits　the　high　dispersion　of　the　basic　Ba　promoter　over　an　electron-withdrawing　GC　support,　and　then　Ba　species　serve　as　structural　promoters　to　stabilize　Ru　with　small　particle　sizes,　which　exposes　more　active　sites　for　N-2　activation.　Additionally,　the　intimate　Ba　and　Ru　interface　enables　facile　electron　donation　from　Ba　to　Ru　sites,　thus　accelerating　N-2　dissociation　to　realize　efficient　NH3　synthesis.　This　work　provides　a　simple　approach　to　modulating　the　Ru-promoter　interface　and　maximizing　promoter　utilization　to　enhance　NH3　synthesis　performance.