The　controllable　catalytic　reaction　plays　a　pivotal　role　in　heterogeneous　catalysis.　Surface-enhanced　Raman　scattering　(SERS)　and　tip　enhanced　Raman　spectroscopy　(TERS)　are　considered　promising　techniques　for　the　study　of　catalytic　reactions　due　to　the　highly　localized　sensitivity　of　SERS　and　the　nanoscale　spatial　resolution　of　TERS.　Herein,　Ag/Au　composite　films　were　employed　as　catalyst　for　in　situ　monitoring　of　the　catalytic　reaction　of　4-nitrobenzenethiol　(4NBT)　to　p,　p＇-dimercaptoazobenzene　(DMAB).　The　catalytic　reaction　of　4NBT　adsorbed　on　Au　film　can　be　manipulated　at　the　nanoscale　using　TERS　by　controlling　the　height　between　the　tip-apex　and　the　sample　surface　in　Ag　tip-Au　substrate　geometry.　According　to　finite　difference　time　domain　(FDTD)　simulations,　the　＇hot　electron＇　induced　by　the　localized　surface　plasmon　is　sufficient　for　promoting　the　catalytic　reaction.　These　findings　provide　a　novel　way　for　controllable　graph　drawing　of　molecules　at　the　nanoscale　level.　(C)　2019　Elsevier　B.V.　All　rights　reserved.