Wilhelm Paul Albert Klingenberg (28 January 1924 – 14 October 2010) was a German mathematician who worked on differential geometry and in particular on closed geodesics.

After the war, he studied mathematics at the University of Kiel, where he finished his Ph.D. in 1950 with Karl-Heinrich Weise, with a thesis in affine differential geometry.

After some time as an assistant of Friedrich Bachmann, he worked in the group of Wilhelm Blaschke at the University of Hamburg, where he defended his Habilitation in 1954.

In 1962 he visited the University of California, Berkeley as a guest of Shiing-Shen Chern, who he knew from his time in Hamburg.

In 1966 he was an invited speaker at the quadrennial International Congress of Mathematicians in Moscow; his talk was on "Morse theory in the space of closed curves".