Transdisciplinary research is the key basis to solve the problems for sustainable development of the human society. Academia Sinica comprises scientists from three major fields: mathematics/physical, life, and humanities/social sciences. Based on this advantage, the Center for Sustainability Science (CSS), Academia Sinica was established in 2012. It aims at promoting the transdisciplinary research on interactive process and mechanism in between human society and natural system. It is expected to not only find the solutions to break the dilemmas encountered by sustainable development of human society, but also provide the appropriate implementation plans. CSS has three major missions: (1) To run the funding program of sustainability sciences on transdisciplinary research; (2) To take charge of relevant international collaborative projects; (3) To propose the policy suggestions on subjects of sustainable development.