This study introduced a carbon footprint (CF) method based on a life cycle assessment to analyze greenhouse gas (GHG) emissions derived from pig production system in China by using national statistical data during 2000-2016. Results showed that the CF of pig production in China was showing a reduction trend. Specifically, the average CFs of unit mass alive pig in the backyard, specialized, medium scale and large-scale farms in China were 1.78 kg CO2-eq/kg, 1.55 kg CO2-eq/kg, 1.65 kg CO2-eq/kg and 1.65 kg CO2-eq/kg, respectively, during 2000-2016. Therein, the feedstuffs production and manure management are the main GHG sources in pig production system in China. The total GHG emissions of the Chinese pig system were slightly decreasing from 128.37 million tons (Mt) CO2-eq in 2000 to 127.08 Mt CO2-eq in 2016, while the pig production quantity was increased by 35.12% during the study period. It implied that the pig production system in China had developed toward a positive effect on GHG emissions reduction in recent years. Moreover, this study also estimates the possible quantity of GHG emissions of Chinese pig sector in 2030 through scenario analysis. The simulated results were ranging from 18.48 to 176.42 Mt CO2-eq/yr, reflecting that the Chinese pig sector still had considerable mitigation potential for GHG emissions. The shift towards intensive pig production, improved feed crop cultivation and manure management systems would be the key points to reduce the GHG emissions of pig production system. This study would contribute to the development of the pig production system in China with a cleaner production approach. (c) 2021 Elsevier Ltd. All rights reserved.