Guillermo von Schulenburg Prado, often referred to simply as Guillermo Schulenburg (June 12, 1916 – July 19, 2009), was the abbot of the Basilica of Guadalupe in Mexico City from 1963 to 1996.
He was the subject of a scandal in 1996, during the beatification of Juan Diego whose canonization he opposed as a "recognition of a cult." He was also quoted by the magazine Ixthus as saying that Juan Diego was "a symbol, not a reality." Aged 80, he retired one month after the scandal.