The local assembly approved a "declaration on the independence of the autonomous republic of Crimea and the city of Sevastopol" with 78 out of 81 lawmakers present voting in favour.
The move by the parliament, which has been declared illegal by the new government in Kiev, appeared to be aimed at creating a legal framework for joining Russia as a sovereign state, AFP reported.
The parliament's press service said in a statement that independence would come into force after the referendum if the result is in favour of Crimea becoming part of the Russian Federation.
The declaration referred to Kosovo's separation from Serbia, adding that "the unilateral declaration of independence of part of a state does not violate any international laws."
If the referendum is in favour of Russia, "the republic of Crimea as an independent and sovereign state will apply to the Russian Federation to join it"