Messi, arguably one of the best footballers in the history of the sport, is accused, along with his father Jorge Horacio, of defrauding Spain of more than €4m (£3.4m).
According to the BBC, the 25 year old and his father are suspected of filing fraudulent tax returns for the 2007-2009 tax year.
A complaint outlining the alleged fraud was filed by prosecutor Raquel Amado at the courthouse in Gava – an affluent Barcelona district where Messi, who receives a net salary of €16m a year from his club, lives.
Messi was apparently unaware of the allegations.
In a statement posted on his Facbook page he said: “We have just [heard] through the media about the claim filed by the Spanish tax authorities. We are surprised about [the] news, because we have never committed any infringement.
“We have always fulfilled all our tax obligations, following the advice of our Tax Consultants who will take care of clarifying this situation.”