Professor Bai joined ANU in 2011 as a Professor of Urban Environment and Human Ecology at the Fenner School of Environment & Society. Prior to her appointment at the ANU, Xuemei was a Senior Principal Research Scientist at CSIRO, a Visiting Professor at Yale University, and Senior Researcher at environmental research institutes in Japan. She is an Adjunct Professor at Beijing Normal University.

Professor Bai's research focuses on several frontiers of urban sustainability science and policy, including the drivers and consequences of urbanisation, structure, function, processes, and the evolution of urban socio-ecological systems, urban metabolism, urban sustainability experiments and transition, cities and climate change, and urban environmental policy and governance.

Professor Bai has authored and co-authored over 100 publications, including several in Nature and Science. She served as a Lead Author for the Millennium Ecosystem Assessment, the Global Energy Assessment, and is a Lead Author for IPBES Global Assessment and IPCC AR6. She has delivered invited lectures and seminars at top academic institutions as well as many international conferences and science/policy forums. She has supervised award-winning PhD and Honours students.

Professor Bai served as an inaugural member of the Science Committee of Future Earth where she has been leading the development of the Urban Knowledge-Action Network, and a Council Member of the International Society of Industrial Ecology. She served as the Vice Chair of the Science Committee of the International Human Dimensional Program for Global Environmental Change (IHDP); Science Steering Committee of IHDP Industrial Transformation Core Project; and Steering Committee of US National Academies Sustainable Cities Initiative. She served on the European Research Council assessment panels for Consolidator and Advanced Grants, and was a member of Global LafargeHolcim Award Jury for 2018. She is a Deputy Editor of Global Sustainability, and serves on the Editorial Board of Current Opinion; Environment; Computer, Environment and Urban Systems; Ecosystem Health and Sustainability; Urbanisation, and the International Journal of Sustainable Cities and Society.

She is a Fellow of Academy of the Social Sciences in Australia since 2017, and was named one of the World's 100 Most Influential People in Climate Change Policy in 2019. She is the 2018 Laureate of the Volvo Environment Prize.