With 80% of votes counted, his National Democratic Party (NDP) looked set to take 27 seats in the 51-seat National Assembly, an absolute majority.
The National Assembly will choose a president within weeks of the parliamentary election.
For Mr Bouterse to stay in power, 34 lawmakers will have to vote for him.
His party currently looks short of achieving that figure, but Mr Bouterse said on Monday that he favoured entering into a coalition.
"It depends on how many votes the population gives us, but regardless it would be good to form a stronger and more stable [government] with those who also think positively," he said.
NDP supporters celebrated at their party headquarters as the preliminary results came in, waving purple flags, dancing and setting off fireworks.
Chandrikapersad Santokhi, the leader of the V7 main opposition coalition, told local media the result was "worse than I had expected".
Mr Bouterse is a powerful but controversial figure in Suriname.
He ruled for seven years after seizing power in a coup in 1980 before stepping down, but briefly ruled again after a second coup in 1990.
In 1999 he was convicted in absentia by a Dutch court for cocaine trafficking, charges he has denied.
As the Netherlands does not have an extradition treaty with its former colony, Mr Bouterse was never jailed.
In 2012 the National Assembly, which was dominated by Mr Bouterse's party, voted to grant the president immunity for alleged human rights abuses committed under his military rule.
He had been charged with involvement in the murder of 15 political opponents in 1982, which he denied.
The probe was led by his now political rival Mr Santokhi, who was the police commissioner at the time.
Preliminary results from Monday's general election in Suriname suggest the party of incumbent President Desi Bouterse has a comfortable lead.