Dry　reforming　of　methane　(DRM),　which　is　a　viable　approach　for　carbon　capture　and　utilization,　is　notably　inclined　towards　carbon　deposition　due　to　the　formation　of　cold　spots,　causing　catalyst　rapid　deactivation,　thereby　limiting　its　industrial　application.　In　order　to　prevent　catalyst　coking,　it　is　imperative　to　improve　the　heat　and　mass　transfer　processes　in　DRM　reactors.　A　foam　reactor　with　hierarchical　pore　structure　was　proposed　in　this　work,　which　is　composed　of　fine　and　coarse　pores　and　avoids　contact　thermal　resistance　due　to　the　contact　of　foam　structures　with　different　pore　sizes.　Based　on　lattice　Boltzmann　model,　this　work　investigated　the　impact　of　hierarchical　pore　structure　on　the　heat　and　mass　transfer,　as　well　as　DRM　reaction　in　Ni/Al2O3　based　foam　reactors.　The　findings　suggest　an　optimal　overall　heat　transfer　coefficient　with　the　variation　of　dcoarse/dfine　under　equal　pumping　power.　Furthermore,　it　reveals　a　synergistic　mechanism　between　the　heat　and　mass　transfer　processes,　identifying　an　optimal　hierarchical　pore　structure　which,　compared　to　uniform　fine　and　coarse　pore　structures,　facilitates　an　enhancement　in　reaction　performance　by　14.1　%　and　13.0　%,　respectively.　This　work　provides　a　theoretical　foundation　and　technical　direction　for　the　design　of　foam　reactors.