According to Brazilian newspaper Folha de S.Paulo, the Portuguese government are probing Scolari over €7 million worth of unpaid taxes that were allegedly unreported by the World-Cup winning coach during his spell in charge of Portugal between 2003 and 2008.
The 65-year-old is also suspected of money laundering involving companies in the Netherlands, United Kingdom, Bahamas and the British Virgin Islands.
However, Scolari rejected the accusations in a statement released by the Brazilian Football Confederation (CBF) on Tuesday.
"I have filed all my tax returns correctly," said Scolari, who recently named his 23-man squad for the upcoming FIFA World Cup.
"In every country that I've worked, I've always claimed my income. I'm absolutely sure that I've filed all my tax returns correctly.
"If there's something wrong, it's not with me. The justice system will narrow the facts."
The news is an unwelcomed distraction for Scolari, who is stepping up preparations for the World Cup in Brazil, which kicks off on June 12.
