Hans Alex Keilson (Dutch pronunciation: [ˈɦɑns ˈkɛilsɔn]; 12 December 1909 – 31 May 2011) was a German/Dutch novelist, poet, psychoanalyst, and child psychologist. He was best known for his novels set during the Second World War, during which he was an active member of the Dutch resistance.

Keilson, having worked with traumatized orphans, mainly wrote about traumas induced by the war. His first novel was published in 1934, but most of his works were published after the war. In 2010, The New York Times 's Francine Prose described Keilson as "one of the world's greatest writers", notably honouring Keilson's achievements in the year in which he turned 101 years old.