Densified　wood　(DW)　is　a　novel　structural　material　with　promissing　application　potential　in　construction　industry　due　to　its　excellent　mechanical　performance.　However,　it　could　also　be　a　disastrous　fuel　contributing　to　the　development　of　fires.　This　work　experimentally　and　numerically　investigated　the　combustion　behavior　of　DW.　The　differences　among　wood　species　(fir,　pine　and　oak)　and　their　char　oxidation　impacts　are　emphasized.　The　experimental　results　indicate　that　DW　has　a　44.7　K　lower　pyrolysis　peak　temperature　on　average,　a　32.2　%　lower　peak　mass　loss　rate,　and　a　8　%　higher　residual　mass　ratio　than　natural　wood　(NW)　in　N2　due　to　the　delignification　process.　The　hemicellulose　and　cellulose　pyrolysis　are　endothermic　in　N2　but　exothermic　in　air.　Wood　pyrolysis　has　an　additional　char　oxidation　reaction　in　air.　The　higher　density　of　DW　leads　to　longer　times　for　ignition　and　flaming　combustion.　DW　presents　a　higher　heat　release　rate　and　average　4.7　MJ　kg−1　higher　effective　heat　of　combustion　of　char.　Two　parallel　pyrolysis　reaction　schemes　based　on　ambiance　are　proposed,　which　well-predict　the　microscale　characterizations　but　fail　to　represent　the　combustion　behavior.　An　optimized　mode　was　developed　by　adding　a　continuous　char　oxidation　reaction　to　the　N2　reaction　scheme,　which　best　predicts　the　combustion　behaviors.　©　2024　Elsevier　Ltd