<p>Peatlands are important carbon reservoirs, yet the mechanisms governing their long-term carbon dynamics remain poorly understood, particularly under combined climatic and anthropogenic pressures. Here, we present comprehensive Holocene records of net carbon balance (NCB) and accumulation rates (AR) from peatlands across mainland China, encompassing alpine, subalpine, and lowland ecosystems. Our results reveal distinct regional trajectories shaped by the interplay of climatic variability and human activity. During the early Holocene (∼11.5–8 kyr BP), peatlands across China exhibited uniform declines in NCB and AR, primarily driven by rapid climatic warming, intensified peat decomposition, and hydrological disturbances. Since the mid-Holocene, carbon dynamics have diverged markedly between regions: alpine peatlands on the Tibetan Plateau and Altai Mountains (TPA) experienced sustained declines in NCB due to continued warming and drying, while intensified human activity became the dominant driver in subtropical South China (SSC) and Northeast China (NEC) peatlands. Specifically, human-induced erosion in SSC subalpine peatlands increased AR but caused significant carbon dilution in peat deposits, thereby reducing NCB. In contrast, lowland peatlands in NEC received substantial inputs of TOC-enriched soils due to agricultural expansion and permafrost thaw, resulting in concurrent increases in AR and stable to rising NCB. These findings highlight the critical role of regional geomorphology, climatic conditions, soil properties, and both the type and intensity of human disturbances in mediating peatland responses to environmental change. Our study has significant implications for global climate mitigation efforts, as it underscores the need for region-specific peatland management strategies to preserve these vital carbon sinks.</p>