A FIFA statement said it had “been made aware of a series of allegations involving the secretary general”.
The Frenchman, who has been in his role at FIFA since 2007, denies the allegations.
United States officials have since indicted those seven and two other FIFA officials on bribery and racketeering charges.
As well as the US inquiry, a Swiss investigation is looking into the bidding process for the 2018 and 2022 World Cups.
Valcke has also faced scrutiny in recent months over his role in an alleged $10m (£6.5m) bribe — an allegation he denies.
United States prosecutors say the money was paid by South Africa to former FIFA vice-president Jack Warner in return for his vote and backing during their successful bid to host the 2010 World Cup.
The money is said to have been transferred to Warner from a FIFA bank account after being reappropriated from South Africa’s World Cup local organising committee budget.
The New York Times and other US media outlets, citing US law enforcement sources, have claimed Valcke was the “high-ranking FIFA official” who signed off the payment.