Dilma Rousseff, a 62-year-old grandmother who acted as energy minister and recently cabinet chief of the outgoing president, will take over the reign of government from outgoing leftist leader Luiz Inacio Lula da Silva.
The outgoing president, who is on his last term, is very popular in the country with 80 percent approval rating. There were rumors that he might be appointed as senior adviser to the new lady president.
Speculation was swirling that he might accept an international post, or stand by as an informal advisor to Rousseff as she runs the country, though he has downplayed those scenarios.
"There is no possibility of an ex-president participating in a government," Lula said when he voted on Sao Paulo's outskirts, where he started out as a factory metalworker and union leader.
Rousseff will have "to form a government in her image. I only hope that she does more than I did," he said.
Reports say Lula is known for his charisma as opposed to Rousseff's reputation as a 'lady with an iron hand'.
But she does have such a reputation for fierce determination that Brazil's media have nicknamed her the "Iron Lady," in the mold of former British prime minister Margaret Thatcher.
She developed her political spine when she started out as an active militant opposed to the 1964-1985 military dictatorship that ruled Brazil.
Brazil's new lady president, who was imprisoned for three years for her underground activism, will take her post in January next year.