Jürgen Walther Ludwig Aschoff (January 25, 1913 – October 12, 1998) was a German physician, biologist and behavioral physiologist.
Together with Erwin Bünning and Colin Pittendrigh, he is considered to be a co-founder of the field of chronobiology.Aschoff's work in the field of chronobiology introduced the idea that shifting one's light-dark cycle can result in harmful effects, such as correlations with mental illness.