At least 642 inhabitants were massacred there by Nazi troops on June 10, 1944, four days after the landing.
They had been gathered in churches and barns as the village was set on fire by the SS Das Reich division.
The killings are believed to be in retaliation for the kidnapping of a German soldier by the French resistance.
A new village was built nearby, but the ruins of the old village are preserved as a memorial and a reminder of the massacre.
Prime Minister Jean Castex declared that the graffiti “stains the memory of our martyrs”.
Mr Macron has vowed to find those responsible and bring them to justice.
Justice Minister Eric Dupond-Moretto said: “Shame on those who did this. Everything will be done to find and judge those who have committed these sacrilegious acts.