Agricultural ecosystems can act not only as a carbon source, but also as a carbon sink. Its importance in mitigating carbon emission has been widely recognized by the international community.Compared with advanced technologies, carbon tax, subsidies, and other economic measures are considered to be relatively simple and feasible to govern climate change. Based on integrated assessment model GOPer-GC (Governance and development policy simulator on global climate model), we constructed international carbon tax scenarios and simulated their effects on agricultural land cover and its carbon emissions from 2008 to 2050. The simulation results showed that cumulative carbon emission due to global agricultural land use change in scenarios 2 and 3 was 49.6 and 23.1 GtC, respectively, which were significantly lower than that in the baseline scenario. This indicated that instead of carbon tax income as a general revenue, carbon tax income as a subsidy for the agricultural sector can reduce carbon emissions of the agricultural land use change. Additionally, the subsidy policy, considering that the forestry sector gets more carbon tax income than farming and animal husbandry sector, significantly reduces carbon emission due to land use change, mainly due to the increase in the conversion of crop land and grassland to woodland. China's carbon sinks, contributed from the conversion of crop land and grassland to woodland, increased obviously in scenario 3. In this scenario, converting cropland and grassland to woodland in China contributed 1.7 GtC and 3.7 GtC of carbon sink respectively. Therefore, for most regions, such as China, the United States and India, increasing the subsidy of the forestry sector will be an effective way to mitigate agricultural carbon emission due to land use change. In the EU, Japan, East Asia, Malaysia, Indonesia, Russia, and Eastern Europe, the same subsidy in crops, livestock, and forestry resulted in a relatively obvious reduction in emission.