Arseniy Yatsenyuk, 33, was economics minister from September 2005 to August 2006, and was appointed foreign minister in March 2007.
The Yulia Tymoshenko bloc and pro-presidential Our Ukraine-People's Self-Defense faction formed on Thursday a majority coalition in parliament, paving the way for the formation of a government. The two blocs also nominated Tymoshenko as prime minister.
Mykola Shershun, head of the Supreme Rada's vote count commission, said 227 parliamentarians had voted for Yatsenyuk, with 226 votes necessary for the approval of the nomination.
Yatsenyuk is a member of the Our Ukraine-People's Self-Defense party.
Ukrainian President Viktor Yushchenko, who had reportedly planned to congratulate Yatsenyuk on his appointment, failed to make an appearance at parliament on Tuesday night.
Parliament is due to hold another session on Thursday.
