Josef Stoer (born 21 June 1934) is a German mathematician specializing in numerical analysis and professor emeritus of the Institut für Mathematik of Universität Würzburg.He was born in Meschede, and earned his Ph.D.
in 1961 at Johannes Gutenberg-Universität Mainz under Friedrich Ludwig Bauer and Klaus Samelson.
He has advised over 20 doctoral students.He is the author (with Roland Bulirsch) of Introduction to Numerical Analysis, a standard reference for the theory of numerical methods.
He has an honorary doctorate from the University of Augsburg (2007) and the Technical University of Munich (1997) and is a member of the Bavarian Academy of Sciences (1981).