A Sao Paulo court rejected an appeal from the Brazilian striker last week and started issuing warrants to freeze the assets, Brazilian media reported.
Last year, Neymar, his family, and related businesses were found guilty of evading 63m reals (€14.2m) in taxes between 2011 and 2013 when he was playing for Brazilian club Santos. He has denied any wrongdoing.
The 23-year-old used the jet to travel to Brazil for World Cup qualifying matches and holidays.
Iagaro Jung Martins, an auditor with Brazil’s tax agency, said that Neymar is unlikely to go to jail if he pays what regulators say he owes.
“He can still appeal that decision, but it is a step forward,” Mr Martins said. “Nothing changed to what was in place last year. If he pays what he owes, the case is closed. Our legislation isn’t too harsh.”
The assets seizure is the latest in a streak of bad news for the Brazilian star off the pitch.
On February 2, Neymar and his father were questioned for three hours in a Madrid court about the player’s transfer to Barcelona.
The case was brought by Grupo Sonda, which invested in Neymar early in his career and was allegedly entitled to 40% of the total transfer amount.
Barcelona maintains the deal cost the club €66.2m.
Santos officially received a payment of €16.5m, with the remainder going to a company owned by Neymar’s father, Neymar Santos.
However, investigations in Spain later showed that Barcelona spent nearly €80.5m to acquire Neymar.
Former and current Barcelona presidents and representatives of Santos were also questioned. The Brazilian club also claims to have been hurt by the transfers.
All parties denied any wrongdoing.
Fellow Barcelona star Javier Mascherano accepted a one-year suspended prison sentence and a fine of €816,000 last month for committing tax fraud of €1.5m.
The plea agreed between the Argentina midfielder’s lawyers and the public prosecutor in December, was processed in a hearing that lasted barely 10 minutes.
In Spain, sentences less than two years are normally suspended unless the guilty party has previous convictions.
The prosecution alleged Mascherano failed to declare over €1.5m in earnings between 2011 and 2013 by ceding his image rights to companies he owns in Portugal and the US.
Mascherano admitted to the two counts of tax fraud against him in October and deposited nearly €1.75m with the tax authorities in September to repay the amount owed plus interest.
Mascherano’s club and international team-mate Lionel Messi faces similar sanctions as he is due to stand trail for tax fraud on May 31.
The recently crowned five-time World Player of the Year and his father have been charged with allegedly failing to declare €4.16m in taxes related to his image rights between 2007 and 2009.
Unlike Mascherano, Messi has not admitted to any crime, insisting it was his father Jorge Horacio who managed his finances, which makes a similar plea with the authorities less likely.