Antoine Geoffroy-Dechaume (7 October 1905 in Paris – 15 April 2000) was a French musicologist, organist and harpsichordist.
As a musicologist he was considered "the leading French pioneer in the field of early music, both in the way it should be performed and in respect for the original scores of 16th, 17th and 18th century composers.
From 1922 to 1937 he served as organist of Notre Dame de Pontoise and from 1937 to 1939 he taught on the faculty of the University of Caen Lower Normandy.
He then took a position at the Conservatoire à rayonnement régional de Poitiers where he led a highly regarded early music group, the Collegium Musicae Antiquae.
The festival notably used a score he had prepared for a revival of Jean-Philippe Rameau's 1733 opera Hippolyte et Aricie.