The Supreme Rada voted twice on Tymoshenko, who briefly served as premier in 2005, after the first vote allegedly failed after a technical malfunction. Both times, President Viktor Yushchenko's flamboyant 'orange revolution' ally received 225 votes. The speaker announced a recess.
The 'orange' camp accused their opponents - the Party of Regions led by acting Prime Minister Viktor Yanukovych - of blocking lawmakers' electronic cards during the vote.
"Those who did this must be brought to account. This is a crime," said Bohdan Gubsky, a member of the Yulia Tymoshenko Bloc.
The process could now start over again with the president proposing that the legislature reappoint Tymoshenko as premier, if the coalition backs her candidacy for a second time.
Tymoshenko, 47, was nominated for the post by a coalition of her eponymous party and the pro-presidential Our Ukraine bloc after the groups won a total of 227 seats in the September elections, one vote above the 226 votes required to form a majority in the 450-seat Supreme Rada.
President Yushchenko approved Tymoshenko, whom he sacked after about eight months at the post of premier in 2005. The two reconciled in the run-up to the parliamentary elections in a bid to end a years-long political crisis in the ex-Soviet state.
Earlier reports said that seven coalition members had refused to back Tymoshenko as the coalition's candidate for prime minister. The parliamentary coalition has also sought key economic portfolios in a new government.
Yushchenko called the snap elections after several members of his bloc defected to the party led by more Moscow-friendly Yanukovych.
The Party of Regions won the largest number of seats in the legislature in the polls, but failed to forge a majority coalition. Yanukovych, Yushchenko's presidential rival in 2004, became prime minister several months after winning the March 2006 polls.