Both anthropogenic activities and climate change can affect the biogeochemical processes of natural wetland methanogenesis. Quantifying possible impacts of changing climate and wetland area on wetland methane (CH₄) emissions in China is important for improving our knowledge on CH₄ budgets locally and globally. However, their respective and combined effects are uncertain. We incorporated changes in wetland area derived from remote sensing into a dynamic CH₄ model to quantify the human and climate change induced contributions to natural wetland CH₄ emissions in China over the past three decades. Here we found that human-induced wetland loss contributed 34.3% to the CH₄ emissions reduction (0.92 TgCH₄), and climate change contributed 20.4% to the CH₄ emissions increase (0.31 TgCH₄), suggesting that decreasing CH₄ emissions due to human-induced wetland reductions has offset the increasing climate-driven CH₄ emissions. With climate change only, temperature was a dominant controlling factor for wetland CH₄ emissions in the northeast (high latitude) and Qinghai-Tibet Plateau (high altitude) regions, whereas precipitation had a considerable influence in relative arid north China. The inevitable uncertainties caused by the asynchronous for different regions or periods due to inter-annual or seasonal variations among remote sensing images should be considered in the wetland CH₄ emissions estimation.