Charles William Schaeffer (born in Hagerstown, Maryland, May 5, 1813; died in Philadelphia, Pennsylvania, March 15, 1896) was a Lutheran clergyman and theologian of the United States.
In 1864, when the theological seminary was established in Philadelphia, he was elected professor of ecclesiastical history, which post he had since held.
He held high office in the councils of his church, and had been one of the trustees of the University of Pennsylvania since 1859, receiving from it the degree of DD in 1879.
Schaeffer was long one of the leaders of the conservative and confessional party in the Lutheran Church.
He took an active part in the establishment of the theological seminary at Philadelphia in 1864, and in the organization of the general council in 1867.