The spellings Belorussia and Byelorussia are transliterations of unofficial alternative names of the country in Russian. Officially, its Russian name is the Republic of Belarus. Belarus was named "Belorussia" in the days of Imperial Russia, and the Russian tsar was usually styled "Emperor of All the Russias — Great, Little, and White".

This practice continued throughout the Soviet era, with the country taking the official name of the "Byelorussian Soviet Socialist Republic". Some Belarusians object to the name "Byelorussia", as it is an unwelcome reminder of the days under Russian and Soviet rule.

In 2002, an informal survey was conducted by the website pravapis.org to see which version of the name was used on a majority of websites. By using Google, the website looked up various terms and it found that "Belarus", the official short form of the name, was used on 93% of websites checked. Spellings "Belorussia", "Bielorussia" and "Byelorussia" were used in 1%–2% of cases.