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Abstract: The peat sequence at Hani in northeastern China accumulated over the past 16calkyr in a percolation mire in which rain water and ground water seeped through the peat system. The molecular compositions of n-alkanes, n-alkanols, and n-alkanoic acids extracted from the Hani peat sequence reveal different responses to the progressive evolution of climate and changes in the nature of the peat-forming vegetation. Long chain length components that originate from the waxy coatings of subaerial vascular plants dominate the n-alkane distributions throughout the Hani peat sequence. The paleoclimate integrity of these biomarker molecules appears to be well preserved. Most of the n-alkanol distributions are similarly dominated by long chain components that indicate their origins from subaerial plants. In contrast, n-alkanoic acid distributions are dominated by secondary components that record the importance of post-depositional microbial activity in this peat sequence, which evidently can be extensive in a percolation mire. Elevated n-alkane P aq values and C23/C29 ratios, which are both molecular proxies for water-loving plants, record an especially moist local climate in the Bølling-Allerød (14.5 to 12.9ka), Younger Dryas (12.9 to 11.5ka), and Pre-Boreal (11.5 to 10.5ka) portions of the Hani peat sequence. Depressed P aq values and C23/C29 ratios and larger n-alkane average chain length values indicate that the Holocene Climatic Optimum (10.5 to 6ka) was a period of warmer climate with lower effective precipitation, which contrasts with evidence of wetter climates in most of East Asia. [Copyright &y& Elsevier]