Roy Wood Sellars (1880 – September 5, 1973) was an Canadian philosopher of critical realism and religious humanism, and a proponent of evolutionary naturalism. His son was the philosopher Wilfrid Sellars. For much of his career he taught at the University of Michigan.
In his 1967 book, Reflections on American Philosophy From Within he described his views on materialism as evolutionary materialism, an extension to his 1922 groundbreaking book Evolutionary Naturalism.
He helped draft the Humanist Manifesto in 1933 and also signed the Humanist Manifesto II in 1973.