Franz Heinrich (Haim) Ollendorf was born in Berlin. In 1924, he joined the Siemens research department in Berlin, working under Reinhold Rüdenberg. From 1928 he taught in the engineering faculty of the Berlin Technische Hochschule. Despite protest from his supervisor and university rector Ernst Orlich, the Nazis forced Ollendorff to resign in 1933. Soon after the dismissal, Ollendorff joined the teaching staff of the Jewish public school in Berlin, moving to Jerusalem when the school and staff transferred there in 1934.