The movie is based on Roger Peyrefitte's book. Peyrefitte studied in religious schools during his childhood, lived older/younger male to male love with a fan of his book, and outed many homosexual celebrities of his time, including his friend Henry de Montherlant, whose book (later a movie) La Ville Dont le Prince Est un Enfant has some coincidences with Les Amities Particulières.
In the source novel, Georges de Sarre is 14 years old and Alexandre Motier is 12 years old. However, the year in which the film was made, Francis Lacombrade (1942-) was 22 years old and Didier Haudepin (1951-) was 13 years old.