The protestors demonstrated on Saturday hoping that a pre-19 August referendum victory could conclusively oust the leader and his entire government.
They rallied in Caracas to celebrate this week's triggering of an expected referendum on the rule of the president.
The march was called to hail Thursday's decision by electoral authorities to call a referendum this year after the opposition collected enough pro-vote signatures.
But a poll date still has to be set, and when it is held is critically important.
Under the constitution, if the referendum is held after 19 August and Chavez loses, his vice president - a loyal supporter - will take over until elections in December 2006.
New elections within month
But if Chavez is recalled before 19 August, new elections will be held within 30 days. The constitution is not clear on whether Chavez can immediately run again in the ballot. This
would be decided by the Supreme Court.
A staunch nationalist, President
Chavez came to power in 1998
"We say to the National Electoral Council, ... the referendum should be 8 August," Juan Fernandez, a member of the opposition Democratic Coordinator coalition, told the rally.
The electoral body was expected to set the poll date on Monday. Opposition leaders are insisting the council adopt the 8 August date it had previously proposed, although some electoral officials are also suggesting 15 August.
Braving rain showers, the marchers chanted "He (Chavez) is going, he's going."
Polls: Chavez to lose
Most opinion polls have shown Chavez would lose a referendum, but he insists he maintains the support of the country's poor majority.
To win, his opponents must match or beat the 3.76 million votes he received in the 2000 election.
Chavez, a firebrand nationalist who won a 1998 election and was re-elected in 2000, battled the referendum for months but on Thursday agreed to contest a vote that could end his
presidency of the world's fifth-largest oil exporter.
During his five years in power, Chavez has been a polarising figure. The poor love him for seeking to distribute Venezuela's oil wealth more fairly.
But Chavez's critics say he has become increasingly dictatorial and is mishandling the economy.