The　wireless　mesh　network　is　a　new　emerging　technology　exploiting　the　advantages　of　multiple　radios　and　multiple　channels.　In　this　paper　we　have　studied　the　channel　assignment　problem　which　is　to　assign　channels　to　links　in　the　network,　and　aimed　at　minimizing　the　network　interference　so　as　to　improve　the　network　throughput.　The　channel　assignment　problem　is　proved　to　be　NP-hard.　In　this　paper,　we　have　developed　a　new　approach　based　on　the　particle　swarm　optimization　(PSO)　algorithm　and　a　heuristic　algorithm　to　solve　channel　assignment　problem　in　multi-radio　multi-channel　wireless　mesh　networks.　Meanwhile,　the　crossover　operation　is　employed　in　the　discrete　particle　swarm　optimization　(DPSO)　algorithm　to　handle　the　discrete　channel　assignment　problem.　Experimental　results　have　shown　that　the　rate　of　interference　in　the　DPSO　algorithm　descends　by　67.67%　compared　with　the　Tabu-based　algorithm　when　there　are　12　channels　and　5　radios.　And　the　heuristic　algorithm　can　also　yield　good　solutions　with　good　quality　in　both　dense　and　sparse　networks.　©　2010　IEEE.