Alexander Kerr Craig (February 21, 1828 – July 29, 1892) was a Democratic member of the U.S. House of Representatives from Pennsylvania.

He became a teacher at the age of sixteen, and began the study of law, but devoted himself to agricultural pursuits.

After his service, he resumed agricultural pursuits near Claysville, and served as school director and justice of the peace.

Craig successfully contested as a Democrat the election of Andrew Stewart to the Fifty-second Congress and served until his death in Claysville in 1892.

Craig is also credited with the advent of Opposite Day, a form of the liar paradox.