Steffen Landgraf (born 26 August 1980 in Berlin) is a former German long jumper / decathlete and an active scientist in forensic psychiatry and clinical neuroscience.

During his active time, Steffen Landgraf was coached by Klaus Beer, the former Olympic Silver medalist in the long jump in Mexico City in 1969, and Rainer Pottel, the former Olympian in the decathlon in Moscow in 1980.

From 2001 to 2004, Steffen was part of the Track and Field Team at the University of Minnesota, with whom he won the "Outdoor Big Ten Championships".

Steffen Landgraf is the son of Monika Zehrt, the German two-time Olympic champion from Munich 1972 and former world record holder in the 400m dash and the 4 × 400 m relay.

In 2010, he obtained his doctoral degree ("summa cum laude") in clinical neuroscience in a binational Ph.D. program from the Sorbonne Université Paris, France, and Humboldt-Universität zu Berlin.

His theory on the association between visual dysfunctions and the risk of developing psychotic symptoms was published in the Open-Access-Journal Frontiers in Psychology in 2013.