Lake Segozero (, ) is a large freshwater lake in the Republic of Karelia, northwestern part of Russia. It is located at . The Segezha is a major outflow from Segozero and it empties to Vygozero. After the hydroelectric power plant was built on Segezha River the surface area of Segozero Lake have risen from 815 kmò to 906 kmò.
The lake was dammed in the 1970s.