He was born in Vienna and died in Pescadero, California. He was married to Mei von Foerster.
Von Foerster studied physics at the Technical University of Vienna and at the University of Breslau, influenced by the Vienna Circle and Ludwig Wittgenstein. He emigrated to the USA in the 1930s and worked at the University of Illinois, Chicago. There he formed the biological computer lab, studying similarities in cybernetic systems in biology and electronics. He worked together with John von Neumann, Norbert Wiener, Humberto Maturana, Francisco Varela, Gregory Bateson and Margaret Mead, amongst many others. He was editor of the five volumes of Cybernetics (1949-1953) and author of more than 100 publications and speaker to conferences all over the world till old age.