The Mont Mégantic Observatory (; OMM) is an astronomical observatory owned and operated jointly by the Université de Montréal (UdeM), and the Université Laval (ULaval). Founded in 1978, the observatory houses the second largest telescope in Eastern Canada after David Dunlap Observatory near Toronto. It is situated at the summit of Mont Mégantic, the highest point of Eastern Canada accessible by car. OMM is about east of Sherbrooke and east of Montreal.