For the residents of over 30 countries, a visa is not required for entry into Russia. In general, residents of those countries can stay on the territory of Russia for from 14 to 90 days without a visa.
Unlimited entry and exit is available to residents of CIS countries: Azerbaijan, Armenia, Belarussia, Kazakhstan, Kyrgyzstan, Moldavia, Tadjikistan, Uzbekistan, Ukraine. If the stay on Russian territory of the citizens of these countries (with the exception of Belarussia) is over 90 days, they will need grounds to be in Russia for a longer period of time – a work permit, patent, studies at a higher education establishment, etc.
The possibility of staying in Russia without a visa for up to 90 days is available to citizens of Abkhazia, Argentina, Brazil, Venezuela, Colombia, Nicaragua, Peru, Uruguay, Fiji, Chili, Ecuador, Souther Ossetia. Inhabitants of Bosnia and Herzegovina, Macao, Cuba, Serbia, Thailand, Turkey and Montenegro can reside in Russia without a visa for up to 30 days. Hong Kong residents can reside for up to 14 days. You can check whether you need a visa at Russia's diplomatic mission in your country. The full list of addresses of Russian embassies and consulates can be found on the Russian Foreign Ministry's website.