Partial official results issued today show that about 75 percent of voters said "no" to plans to impeach Basescu, who had described the balloting as a "referendum of trust."
Basescu said it is now clear that a majority of Romanians stand behind his efforts to reform the electoral system with the aim of stamping out corruption.
The turnout was some 44 percent of Romania's 18 million voters.
The parliament suspended Basescu on April 20, accusing him of violating the constitution.
Basescu has responded that opponents are resistant to his anticorruption reforms.
The European Union responded today to the vote by urging Bucharest to resume its efforts to fight corruption.
In a statement, European Commission President Jose Manuel Barroso said he hopes the outcome will help Romania move forward with judicial reforms and antigraft efforts.
Barroso said Romania must deliver on commitments it made when joining the EU.
Five parties, including that of Prime Minister Calin Popescu Tariceanu, orchestrated the referendum.
They reportedly have conceded defeat in the vote.
had reflected the strong rebuke of the impeachment planners within hours of the polls closing on May 19.
(compiled from agency reports)