Abstract: Difference in aroma componets between the Pu-erh teas fermented with adding different exogenous carbon source, including xylose, sucrose and pectin, and the control one was analyzed by using simultaneous distillation extraction (SDE) and capillary gas chromatography-mass spectrometry (GC-MS) .Results showed that the kinds of aroma components of the teas fermented with adding exogenous carbon source were much more than those of the control one, 66, 72, 76 and 72 kinds of aroma components were identified in control group, xylose group, sucrose group and pectin group respectively.The control group had the most contents of alcohol, while the other three had more aldehyde, ketone and heterocyclic compounds.The sucrose group had myrtenol, lupeol, decanal and eucarvone which the other three groups didn't have, the content of cyclosativene of pectin group was significantly higher than others.