The fast-food giant, dogged by lawsuits and a documentary blasting the fat content of its food, made the announcement Tuesday.
It said 20,000 restaurants would begin serving Big Macs, Quarter Pounders and other fare with a label detailing calories, grams of fat and a chart with the government's recommended daily intake, the New York Times said.
McDonald's offers a brochure with that information but is the first of the large chains to label the food.
Michael Jacobson, executive director of the Center for Science in the Public Interest, said the move doesn't go far enough.
He said the labels, as proposed, will be confusing to customers. Jacobson supports a bill by Sen. Tom Harkin, D-Iowa, to require restaurant chains to put nutritional information on menu boards so consumers can see what's in the food before buying it.
A lawsuit still pending blames McDonald's for making people obese.
The 2004 film "Super Size Me" highlighted what eating only McDonald's food for 30 days would do to a person's body.