Kexholm County (Swedish: Kexholms län, Finnish: Käkisalmen lääni) was a county of the Swedish Empire from 1634 to 1721, when the southern part was ceded to the Russian Empire in the Treaty of Nystad.

The ceded parts of the County of Viborg and Nyslott and the County of Kexholm were at first part of the Saint Petersburg Governorate, but in 1744 they were reconstituted with new conquests into the Russian Vyborg Governorate, which also became known as Old Finland.

After the Russian victory in the Finnish War of 1809, Sweden ceded all its territory in Finland to Russia by the Treaty of Fredrikshamn.

As part of the Russian Empire Finland came to constitute a separate grand duchy.

In 1812 Russia made the territories of the Vyborg Governorate part of the new Grand Duchy of Finland as Viipuri Province.