Bill Nichols (born 1942) is an American film critic and theoretician best known for his pioneering work as founder of the contemporary study of documentary film. His 1991 book, Representing Reality: Issues and Concepts in Documentary, applied modern film theory to the study of documentary film for the first time. It has been followed by scores of books by others and by additional books and essays by Nichols. The first volume of his two-volume anthology Movies and Methods (1976, 1985) helped to establish film studies as an academic discipline.

Bill Nichols is Professor Emeritus in the Cinema Department at San Francisco State University and Chair of the Documentary Film Institute advisory board.