Sugarloaf Mountain is a peak situated in Rio de Janeiro, Brazil, at the mouth of Guanabara Bay on a peninsula that sticks out into the Atlantic Ocean. Rising above the harbor, its name is said to refer to its resemblance to the traditional shape of concentrated refined loaf sugar. It is known worldwide for its cableway and panoramic views of the city.

The name Sugarloaf or Sugar Loaf applies to numerous raised topographic landforms worldwide: mountains, hills, peaks, summits, buttes, ridges, rock formations, bornhardt, inselberg, etc. Landforms resembling the characteristic conical shape of a sugarloaf were often so named. According to the United States Board on Geographic Names, there are over 200 such designations in the United States alone.