MoS2　on　polycrystalline　metal　substrates　emerges　as　an　intriguing　growth　system　compared　to　that　on　insulating　substrates　due　to　its　direct　application　as　an　electrocatalyst　in　hydrogen　evolution.　However,　the　growth　is　still　indistinct　with　regard　to　the　effects　of　the　inevitably　evolved　facets.　Herein,　we　demonstrate　for　the　first　time　that　the　crystallography　of　Au　foil　substrates　can　mediate　a　strong　effect　on　the　growth　of　monolayer　MoS2,　where　large-domain　single-crystal　MoS2　triangles　are　more　preferentially　evolved　on　Au(100)　and　Au(110)　facets　than　on　Au(111)　at　relative　high　growth　temperatures　(＞680　degrees　C).　Intriguingly,　this　substrate　effect　can　be　weakened　at　a　low　growth　temperature　(similar　to　530　degrees　C),　reflected　with　uniform　distributions　of　domain　size　and　nucleation　density　among　the　different　facets.　The　preferential　nucleation　and　growth　on　some　specific　Au　facets　are　explained　from　the　facet-dependent　binding　energy　of　MoS2　according　to　density　functional　theory　calculations.　In　brief,　this　work　should　shed　light　on　the　effect　of　substrate　crystallography　on　the　synthesis　of　monolayer　MoS2,　thus　paving　the　way　for　achieving　batch-produced,　large-domain　or　domain　size-tunable　growth　through　an　appropriate　selection　of　the　growth　substrate.