The Lotta (Finnish: Luttojoki or Lutto, Northern Sami: Lotto or Lohttu, Skolt Sami: Lått, Russian: Лотта and Norwegian: Lotta) is a river that is part of the watercourse of the Tuloma.

Before the Pechenga area was ceded to the Russians, the entire river was within Finland's borders.

From there, the river flows eastward, occasionally hugging the border between Inari and Sodankylä.

Near Raja-Jooseppi, it enters Russia, turns northeast and empties into the western side of the Verkhnetulomskoye Reservoir, which is drained by the river Tuloma.

The river's most significant tributary on the Finnish side of the border is the Suomu.