Abstract: This peat sedimentary sequence was systematically investigated with lipid molecular stratigraphy by gas chromatography-mass spectrometer (GC-MS). A variety of molecular fossils are found in this peat profile, including n-alkanes, n-alkanols and n-fatty acids and so on. The n-alkenes are from C18 to C28, hav-ing a maximum at C27, with s second dominance at C23 or C25. In contrast to the n-alkenes analysed, the n-alkanes are characterized by the dominance of heavy-molecular-weight homologues (>C22) at the same depth. According to the analysis, we found the high carbon number n-alkenes possibly are mainly derived from higher plants, while algae and microorganisms are secondly. The ratios of low molecular number to high molecular number n-alkenes(∑C21-/∑C21+) and the ratios of n-alkenes to the corresponding carbon number n-alkanes such as C24:1/C24:0 and C23:1/C23:0 show the regular variations. ∑C21-/∑C21+ has the same trend as the ratios of low molecular number to high molecular number n-alkanes (L/H-ALK) on the whole; on the contrary, C24:1/C24:0 and C23:1/C23:0 have an opposite trend. These results indicate n-alkenes especially these middle carbon number n-alkenes give microbial hydrogenation under the reductive condition resulting from the climatic change such as temperature. The results show n-alkenes proxies seem to bear significant climate information and possibly indicate temperature changes in the northeastern Qinghai-Tibet Plateau during the Holocene. In addition, (C26 +C27 +C28)/(C23+C24 +C25) n-alkene ratios display a defi-nite corresponding relationship with the vegetation in the region, possibly suggesting these n-alkenes not only have a relationship with the vegetation, but also are capable of microbial degradation of different vege-tation species. Climatic information from these n-alkens proxies is consistent with previous paleoclimate signals extracted from n-alkanes, n-alkanols and n-fatty acids of the same peat profile. These indicate n-al-kenes proxies can be an important proxy for studying the paleoclimate and global change.