The William E. Simon Prize for Philanthropic Leadership is an annual award given by the William E. Simon Foundation in honor of its founder, former Secretary of the Treasury and financier William E. Simon, and administered by the Philanthropy Roundtable.

William Edward Simon was an American businessman and philanthropist who served as the 63rd United States Secretary of the Treasury. He became the Secretary of the Treasury on May 9, 1974, during the Nixon administration. After Nixon resigned, Simon was reappointed by President Gerald Ford and served until 1977 when President Jimmy Carter took office. Outside of government, he was a successful businessman and philanthropist. The William E. Simon Foundation carries on this legacy. He styled himself as a strong advocate of laissez-faire capitalism. He wrote, "There is only one social system that reflects the sovereignty of the individual: the free-market, or capitalist, system".