Dr. Nahallage obtained her undergraduate degree from the faculty of Applied Sciences at theUniversityofSri Jayewardenepura. She joined the Department of Sociology and Anthropology in 1996 and from 1998 she was appointed as a permanent lecturer. She obtained her Master of Science and Doctor of Science Degrees from the Primate Research Institute,Kyoto University,Japan, where she specialized in Primatology.
At present she teaches physical anthropology to undergraduate students in the Department of Sociology and Anthropology. In addition she has been serving as a visiting lecturer in the Department of Forensic Medicine at the faculty of Medical Sciences, University of Sri Jayewardenepura; Department of Musicology, University of Visual Arts and Performing and Postgraduate Institute of Archaeology, Kelaniya University. Furthermore she serves as a primate resource person to various government departments and private companies in the country. Additionally she serves as an adjunct faculty member at the National Institute of Advanced Studies, Indian Institute of Science campus, Bangalore, India.