He is former Professor and Head, Department of Botany & Microbiology and Dean, Faculty of Life Sciences at Gurukul Kangri University, Haridwar. He has had teaching and research stints at Panjab University, Chandigarh and Guru Nanak Dev University, Amritsar. He has also been a Visiting Professor at University of Delhi.
Dr. Purshotam Kaushik has been the Principal Investigator of the project Environmental Biology of the Himalayan Orchids conducted by Ministry of Environment and Forests, Government of India, and also for a project on Lectins conducted by UGC He has visited Universities of London, Cambridge & Kew (United Kingdom) and Institute Pasteur, Paris (France).
Dr. Purshotam Kaushik has supervised 30 Ph.D. students and has published over hundred research papers. He has authored five original research monographs and two editions of the edited book Indigenous Medicinal Plants, Including Microbes and Fungi. He has also written a textbook on Introductory Microbiology. He is the President of Academy of Plant Sciences, India and has also been an elected Syndic of Gurukul Kangri University and a member of Board of Management and that of Academic Council. He has also been a member of Board of Studies of many Universities. He has been associated with designing and starting M.Sc. Microbiology courses at Gurukul Kangri University from the very inception of the courses.