He studied archaeology, classics and ancient history and got his PhD in 1923 under Ferdinand Noack. He worked as a research assistant at the Max Freiherr von Oppenheim-Stiftung in Berlin, and since 1929 in the Ancient Near East department of the National Museums in Berlin.
In 1948 he became a professor at the Free University of Berlin.
In 1955 he had done excavations in Syria.
In 2007 The Museum of the Ancient Near East has dedicated a memorial exhibition to Moortgat, marking the 110th anniversary of his birthday .
