John William Wallace (February 17, 1815–January 12, 1884) was an American lawyer and the seventh reporter of decisions of the United States Supreme Court, serving from 1863 to 1874.
Born in Philadelphia, he graduated from the University of Pennsylvania in 1833 and studied law under his father. While librarian to the Law Association of Philadelphia, he compiled three volumes of decisions of the Third Circuit Court of Appeals, which sat in that city. He wrote The Reporters on English reporters and cases, a book which was often reprinted and made his reputation. His twenty-three volumes of reports of the Supreme Court's cases are highly respected for their quality. He also served as president of the Historical Society of Philadelphia. Wallace died in his hometown.