Nathan Paul Feinsinger (September 20, 1902 – November 3, 1983) was a professor of law at the University of Wisconsin Law School. He mediated and arbitrated a number of strikes, and served as general counsel to the Wisconsin Labor Relations Board and associate general counsel to the National War Labor Board (WLB). Feinsinger is best known for his mediation efforts in the 1944 telephone operators strike, the 1947 pineapple workers strike, the 1952 steel strike, and the 1966 New York City transit worker strike.