Constantine von Schäzler (b. at Ratisbon, 7 May 1827; d. at Interlaken, 9 September 1880) was a German Jesuit theologian.
He entered the Catholic Church at Brussels on 10 October 1850, and began the study of theology.
In 1857 he left the Jesuits and went on with his studies at Munich where in 1859 he took the degree of Doctor of Theology.
In 1861 he became a tutor in the seminary at Osnabrück; in 1862 privatdozent in the history of dogma at Freiburg; in 1866 archiepiscopal councillor.
During the First Vatican Council (1869–70) he was at Rome as theologian to Bishop Josef Fessler; in 1873 he settled at Rome; in 1874 he was made a domestic prelate and was employed as consultor to various congregations.