Abstract: Taking the leaves of 8 tree species in Beijing as the research object, TG-DTG curves were obtained using TGA/DSC3+synchronous analyzer, to acquire pyrolysis parameters at each stage. The combustibility of the 8 tree species was ranked from three aspects: four-dimensional combustibility, pre exponential factor and activation energy, and principal component analysis, and the optimal fire-resistant tree species was selected. The results show that, based on ignition temperature calculations, the combustibility ranking of the 8 tree species is: Pinus bungeana>Sophora japonica>Pinus armandii>Quercus suber>Juiperus communis>Pinus tabuliformis>Robinia pseudoacacia>Populus tomentosa; Based on activation energy calculations, the ranking is: Quercus suber>Pinus tabuliformis>Robinia pseudoacacia>Pinus bungeana>Juiperus communis>Pinus armandii>Sophora japonica>Populus tomentosa; According to principal component analysis, the ranking is: Pinus bungeana>Quercus suber>Pinus tabuliformis>Pinus armandii>Robinia pseudoacacia>Juiperus communis>Sophora japonica>Populus tomentosa. Since Populus tomentosa has the highest ignition temperature and activation energy, and the lowest principal component score, it can be selected as the optimal fire-resistant tree species.

Key words: thermogravimetric analysis, four dimensional combustibility, principal component analysis, forest fire prevention