Small ponds are important methane (CH 4 ) sources. However, current estimates of CH 4 emissions from aquaculture ponds are largely uncertain due to data paucity, especially in China�the largest aquaculture producer in the world. Here, we present a nationwide metadata analysis with a database of 55 field observations to examine total CH 4 emissions from aquaculture ponds in China. We found that the annual CH 4 fluxes from aquaculture ponds are much larger than those from reservoirs and lakes. The total CH 4 emission from aquaculture ponds is 1.60 ± 0.62 Tg CH 4 yr −1 , with an average growth rate of ∼0.03 Tg CH 4 yr −2 during the period 2008−2019. Compared with global major protein-producing livestocks, aquaculture species have a lower (63%) emission intensity, defined by the amount of CH 4 emitted per unit of animal proteins. Our study highlights the essential contribution of China's aquaculture ponds to national CH 4 emissions and the lower environmental cost of the aquaculture sector for future animal protein production. More field measurements with multi-scale observations are urgently needed to reduce the uncertainty of CH 4 emissions from aquaculture ponds.