James, who moved to Bayern Munich last year, is accused of having evaded €6.35 million in taxes, mainly linked to his image rights, and would have to pay that amount plus a fine and interests for a total of €11.65 million, it reported.
Citing sources close to the case, the daily said James was transferred to Real Madrid from Monaco for €80 million mid-2014, but that year he registered as a non-resident.
Tax authorities, though, reportedly believe he should have registered as a resident, which means he should settle the difference, or €6.35 million, related to his salary and the sale of image rights.
Spain's tax authorities refused to comment when contacted by AFP.
The 27-year-old, who won the Golden Boot for the top goal scorer in the 2014 World Cup, joins a long list of other players who have got on the wrong side of Spain's taxman.
Some have reached deals, like Cristiano Ronaldo, who recently moved to Juventus from Real Madrid and accepted to pay 18.8 million euros and a two-year jail sentence he won't have to serve.
FC Barcelona's star Lionel Messi, though, went to court where he was fined €2.1 million for tax fraud and given 21 months in jail, which was subsequently converted into another fine.