This is reported by Yle, which has published satellite images from the scene.
The new military base is being built in the village of Novaya Vilga in the Russian republic of Karelia, about 180 kilometers from the border with Finland.
Finnish military expert Marko Eklund, who has a background in Finland's military intelligence service, tells Yle that he estimates that the future base will have capacity for between 4,000 and 6,000 soldiers.
According to Yle, it is the first new military base that Russia has built in the region in several decades.
