Måna or Måne is a river in Tinn, Norway; it flows from Møsvatn through Vestfjorddalen and Rjukan to Vestfjorden in Tinnsjå. It is part of the Skiensvassdraget drainage basin.
The river has several power stations, Vemork and Såheim being the largest. It also feeds to the waterfall Rjukanfossen, that is released once a year.