William Green Jr. may refer to:
- William Green Jr. (chaplain), 26th and current Chief of Chaplains of the United States Army.
- William J. Green Jr., a Democratic member of the U.S. House of Representatives from Pennsylvania from 1949 to 1963.
- William R. Green Jr., was a judge of the United States Board of Tax Appeals (later the United States Tax Court) from 1925 to 1929.