Methane (CH₄) is the most abundant hydrocarbon in the atmosphere, only second to carbon dioxide (CO₂) as a greenhouse gas. Wetlands are an important source of methane and play an important role in the global carbon cycle. They account for 70% of all natural methane emissions and 24.8% of global methane emissions. The Qinghai-Tibet Plateau (QTP) has an average elevation of more than 4000 m and contains one-third of China's wetlands. In recent decades, due to global warming and increased precipitation, methane emission rate and wetland area in the region have undergone great changes, so the long-term change of CH₄ emissions is still largely uncertainty. In this study, the TRIPLEX-GHG model was used to simulate the dynamic characteristics of CH₄ emissions from wetlands on the QTP from 1978 to 2008. The results showed that: (1) CH₄ emission rate in QTP wetlands were gradually increasing from 1978 to 2008. (2) CH₄ emission rate in most wetland areas of the QTP was 0-6.13 g CH₄ m^-2a^-1 and in some wetland areas of northeast QTP was 6.14-20.19 g CH₄ m^-2a^-1. The higher CH₄ emission rate distributed in the wetland areas of the southern QTP was 56.14-74.97 g CH₄ m^-2a^-1. (3) Total CH₄ emissions in 1978, 1990, 2000, and 2008 were 0.21, 0.23, 0.27, and 0.32 Tg CH₄ a^-1, respectively. The analyses indicated that although the CH₄ emission rate increased, the wetland area decreased from 1978 to 1990, therefore, CH₄ emissions did not change significantly in this period. Due to the continuous increase of precipitation and glacier melting, the wetland area gradually increased after 2000. With the combination of increasing wetland area and wetland CH₄ emission rate, the total CH₄ emissions of the QTP wetlands had a continuously creasing trend.