Antoni Stefan Koper (September 6, 1906 – June 13, 1990) was active in the Polish resistance movement during World War II and served as a lieutenant in the Polish Home Army. He helped rescue Jews from the Warsaw Ghetto and fought in the Warsaw Uprising. After escaping from a Nazi prison camp, he first fled to London, and then emigrated to the United States. There, he worked for the Defense Language Institute, United States Information Agency, and the Voice of America. He died of cancer in 1990.