Since 2013, Li Long has been deputy director of the Beijing Key Laboratory of Biodiversity and Organic Farming at China Agricultural University (CAU). Long is also professor at the College of Resources and Environmental Sciences Sciences at CAU, where he leads the Research Group for Biodiversity and Resource Utilization.

Long led numerous large research projects, including on integrated agronomic practice research and applications of crop diversification toward enhancing productivity and soil fertility. His research explores how crop diversity maintains multi-functionality of agroecosystems, how to efficiently use resources in intercropping systems systems, and how crop species diversity maintains the temporal stability of productivity for agroecosystems.

Long holds a PhD in plant nutrition and completed a postdoc on soil science and plant nutrition at the University of Western Australia.