Spokesman Steffen Seibert said Monday Merkel originally thought she had a bad bruise but doctors told her last week she probably suffered a fracture to her pelvis and ordered her to rest, the New York Times reported.
Merkel was injured during the Christmas holiday period.
"She fell while cross-country skiing," Seibert said. "We do not believe she was going very fast."
Seibert said all of Merkel's scheduled travel plans were canceled, as were several meetings in Berlin.
He said the chancellor will work from home and plans to lead the first meeting of her Cabinet in person when it convenes Wednesday.
"She is, of course, at work, and every day," Seibert said.