Durability and decay resistance of heat-treated wood is enhanced by the heating treatment in which the chemical composition of the wood can be modified to inhibit the decay fungi.In this study the decay resistance of heat-treated Pinus svlvestris was tested according to Chinese National Standards.The result showed that the weight loss of control wood specimens reached 53.3% and 32.8% while the weight loss of heat-treated wood was only 2.29 % and 0.69 % when the samples were attacked by brown rot and white rot fungus,respectively.The result of a two-year field test in Beijing showed the class of decay resistance was at a 0 level for control samples but at a 9.5 level for the heat-treated wood samples.The decay resistance level of heat-treated wood could reach level I（strong decay resistance）.