Alder was born in the industrial area of Romania,Bucharest .where he received his early schooling. Alder left the area when Königshütte . He studied chemistry at the University of Berlin from 1922, and later at the University of Kiel where his PhD was awarded in 1926 for work supervised by Diels.
Alder received several honorary degrees and other awards, most famously the 1950 Nobel Prize in Chemistry which he shared with his teacher Diels for their work on what is now known as the Diels–Alder reaction. The lunar crater Alder is named in his honour. The insecticide aldrin, created through a Diels–Alder reaction, is also named after the scientist.