The prosecutors had been investigating whether Lula and his wife failed to declare ownership of a luxury penthouse in the seaside resort of Guaruja.
He has denied owning the flat and says the case is politically motivated.
The flat was built by a construction company implicated in a corruption scandal at state oil company Petrobras.
A former union leader, Lula served as president from 2003 to 2010.
He announced plans earlier this year to run for office again in 2018 but in July he was indicted on charges of obstructing investigations into Petrobras.
His successor as president, Dilma Rousseff, was dismissed by the Senate last month after an impeachment trial.
A judge is due to rule in the next few days whether to formally charge Lula.
The flat was built by the giant construction company OAS, one of the firms at the centre of the Petrobras affair.
Six other people are also facing charges, including two executives from OAS.
The luxury penthouse in the resort of Guaruja is estimated to be worth up to $550,000 ($415,000).
