Monnaz is a small village in the hollow of the Morges river, 3 km away from the capital town of the district (Morges). From Monnaz there is a trail along the Morges river down to Morges or Vufflens-le-Château.
The territory of the commune borders on the commune of Vufflens-le-Château, its prestigious neighbour in the West, Vaux-sur-Morges in the North, Saint Saphorin in the East and Echichens in the South.
Being the first village of the “Vallée sèche” (dry valley) where there are no bars, restaurants of cafés, Monnaz benefits from a bypass road that prevents the village from the nuisance of the traffic coming from the road Apples-Morges.
This calm situation nearby Morges attracts a lot of residents working in the Lake Geneva region. They settle in Monnaz in order to profit from the ideal situation.
Originally, Monnaz was under the rule of the lordship of Montricher, after this it belonged to Guillaume de Vulliermin, bourgeois of Morges, of whom there is still the emblem on the gable of the church. This church was entirely renovated in 1998. It was the family Guillaume de Vulliermin who gave the commune its emblem.