The report hit newsstands today as Neymar lined up for Barcelona against Juventus in the Champions League final in Berlin.
The magazine indicated the taxman was calling for audit records from N&N Consultoria Esportiva e Empresarial, a firm run by the player's parents.
The report said the tax authorities wanted to check the origin of some 115 million reais (some USD 38 million) in "atypical movements" of cash sums to the firm which Barcelona reportedly paid over to the company between 2011 and 2013.
Last month, Santos said they had filed a complaint with FIFA against Neymar, his father, his company and Barcelona for short-changing them on the transfer.
Also Read
Santos president Modesto Roma Junior says a Spanish investigation into alleged tax fraud in the move revealed that the true fee paid was at least 83.4 million euros (USD 91.5m) -- far higher than the 57 million euros (USD 62m) that Barca insist they paid overall.
Spanish investigators have accused Barcelona of concealing the full amount paid for Neymar by splitting it between a number of different contracts with the player and Santos.
The transfer has already been the subject of an anti-corruption probe in Spain, where the league champions are accused of defrauding the Spanish tax man of 12.7 million euros.