Born into a farmers' family in Muzaffarnagar district in Uttar Pradesh in 1932, GD Agarwal graduated from University of Roorkee (present-day IIT Roorkee). He started his career as a design engineer in the Uttar Pradesh state Irrigation Department and went on obtain a doctorate in environmental engineering from the University of California at Berkeley.
He was a faculty member of IIT-Kanpur, a member of the Central Pollution Control Board, and an honorary professor of environmental sciences at the Mahatma Gandhi Chitrakoot Gramodaya Vishwavidyalaya, in Chitrakoot, Madhya Pradesh.