The South American Plate is a continental tectonic plate covering the continent of South America and extending eastward to the Mid-Atlantic Ridge.

The easterly side is a divergent boundary with the African Plate forming the southern part of the Mid-Atlantic Ridge. The southerly side is a boundary with the Antarctic Plate and the Scotia Plate. The westerly side is a convergent boundary with the subducting Nazca Plate. The northerly side is a boundary with the Caribbean Plate.

On its western edge the Farallon Plate has been subducting under the South American Plate since the Jurassic period. The remains of the Farallon Plate (currently known as the Cocos Plate) and the Nazca Plate are still subducting under the western edge of the South American Plate.