Livestock manure is one of the main sources of agricultural greenhouse gas(GHG)emissions. Proper management of livestock manure can reduce GHG emissions and mitigate environmental pollution at the same time;however,the mitigation potential of optimal livestock manure management is not clearly stated. In order to estimate the mitigation potential of pig manure management,Hubei province in China is used as a demonstration place. Based on field surveys and natural conditions,the appropriate manure management mode for each farming scale in Hubei is chosen. The protocols for estimating GHG emission factors proposed by the Intergovernmental Panel on Climate Change(IPCC)is used to analyze current GHG emission factors and optimal scenarios for pig manure management,and then predict the mitigation potential of GHG emissions. Under optimized pig manure management,for the same farming scales and patterns in 2012,4 683kt CO_2- eq of GHG emissions could be reduced in Hubei. Meanwhile,the methane(CH_4)emission factor reduced to 29.12% of the current value and the nitrous oxide(N_2O)emission factor decreased 34.13% compared to current values. In order to reduce GHG emissions,manure management for scatter-fed pigs should control CH_4 emissions and scale farming should focus on reducing N_2O emissions. The most effective measure to reduce GHG emissions in mountain areas in western Hubei is to adjust manure management for scatter- fed pigs and in other regions is to optimize manure management for scale farming pigs. Appropriately selected pig manure management combined with regional natural conditions and breeding scales is an effective means to mitigate agricultural GHG emissions.