The pro-Western leader, whose popularity has sunk to an all-time low with the struggling economy and continual political infighting, had hoped to put off the election until the end of his current term, next January.
Under the Ukrainian constitution, parliament has exclusive right to set election dates. After 401 of 450 lawmakers voted in favor of the early date, the presidential administration said Yushchenko would appeal to the Constitutional Court to contest the decision.
Yuriy Miroshnichenko, a lawmaker with the Party of Regions, led by Yushchenko's rival Viktor Yanukovych, said the president's efforts to contest the election date would fail. He called the decision "perfectly legal" and in line with the constitution.
However, other lawmakers suggested that as most members of the Constitutional Court support the president, he may still manage to have the date put off to January 17, 2010.
Wednesday's debate in the Supreme Rada was focused on whether the election date was subject to constitutional amendments made after Yushchenko came to power, which would allow the president to see out his complete term, or whether it should be based on the rules applicable at the time Yushchenko assumed office after the 2004 "Orange Revolution".
On Tuesday, the president proposed constitutional amendments to create a second house of parliament, and to give him veto rights over certain government decisions. Under the current system, the division of powers between prime minister and president are often ambiguous, leading to frequent disputes and power struggles.
Yushchenko's weak political position has been compounded by the shrinking economy, which declined by more than a quarter year-on-year in January-February, weighed down by low prices for the country's key exports, metals and chemicals. The national currency, the hryvnia, has lost much of its value, and ongoing disputes with Russia over natural gas have also stoked political tensions.
The president's former "Orange Revolution" ally, Prime Minister Yulia Tymoshenko, now an arch-rival, is likely to run against the president at the next election, as well as Yanukovych.
