Abstract: Essential oilswere obtained from the bark of ten species of Populus p lants, namely P. ×xiaozhuanica cv.‘Baicheng-2’, P. sim onii ×P. nigra, P. russk ii, P. berolinensis, P. pseudo-sim onii, P. pseudo2sim onii ×P.nigra, P. ussu riensis, P. stalinetz, P. alba ×P. berolinensis and P. sim onii by means of steam distillation technique. The chemical constituents of the oilswere separated and identified by gas chromatography-mass spectrometry(GC-MS) , and 19, 22, 29, 20, 10, 36, 20, 14, 16 and 10 components were separated, respectively, of which15, 21, 27, 18, 9, 33, 17, 11, 13 and 9 componentswere identified. The hexanal, furaldehyde, salicylaldehyde,(E, E) -2, 4-hep tadienal and linoleic acid were extracted from all the ten pop lar trees bark’s essential oil, theamounts of salicylaldehyde in all of them were more than 12. 16% , and especially in P. sim onii, 90. 15%. Themain constituents of the ten essential oilswere aldehydes, esters, alkanes etc. , the percentages of identified components from the total essential oil were 95. 06% , 98. 34% , 96. 91%, 91. 08% , 100% , 96. 00% , 90. 69% ,89. 65% , 95. 31% and 99. 55% respectively.