During 1995-2013, the carbon emissions for farmland uses in Pingdu County (in Shandong Province, China) were calculated by selecting the main sources of emissions and establishing a measurement system for the sources, including indirect carbon emissions for agrochemical inputs, direct N₂O emissions for N fertilization, carbon emissions for energy consumption and straw burning, and CH₄ and N₂O emissions for livestock farming. The changes in carbon intensity were calculated based on the changes in agricultural output value, and the changes in the carbon sustainability index were calculated based on the carbon emissions of the main sources and carbon absorption by the main crops. The results were as follows: (1) The order of annual mean carbon emissions was agrochemical materials (22.50 ten thousand tons) > livestock farming (17.41 ten thousand tons) > straw burning (6.62 ten thousand tons). The carbon emissions for straw burning showed an increasing trend, whereas the emissions from the other sources showed a decreasing trend. (2) The increasing rate for the agricultural output value exceeded that of total carbon emissions, with the carbon emissions per agricultural output value decreasing from 1.24 t/Yuan in 1995 to 0.35 t/Yuan in 2013 (annual average decrease of 0.0459 t/Yuan). (3) The carbon sustainability index had an annual average increasing rate of 7.12%. This trend indicated that the carbon absorption by crops was greater than the carbon emissions from the farmland processes. Overall, this study not only provides an understanding of carbon emissions and a scientific basis for sustainable development of farmland in small-or medium-scale regions in eastern China, but it also promotes the reduction of agricultural carbon emissions in China. In addition, this study could provide basic information for the investigation of Land-Use and Land-Cover Change and Carbon Cycle of International Human Dimensions Programme on Global Environmental Change.