The carbon cycle is one of important biogeochemical cycle in Earth system, which is tightly coupled with climate change. As two largest CO2 emitters, China and USA face great challenges in reducing CO2 emission and enhancing carbon sequestration. This requires jointed efforts from not only leaders of both countries but scientists across the Pacific. In order to provide scientific base for carbon emission and sequestrations, both USCCC and ChinaFLux are committed to gain better understandings of regional carbon cycle by promoting data sharing, cross-site syntheses, and cross-country collaborations. This symposium aims at updating our progresses in this field and to promote academic interactions among members of USCCC, ChinaFlux and other relevant stakeholders.