Blatter, who, along with vice president Michel Platini, faces a long suspension, arrived at FIFA's base in Zurich in a black Mercedes and made no comment as he entered.
Before the hearing, Blatter, 79, wrote a letter to FIFA's 209 members calling the FIFA ethics commission's investigators "the inquisition".
Blatter is under criminal investigation in Switzerland over a two million Swiss francs ($2 million/1.8 million euros) payment made to Platini in 2011 for work carried out about a decade earlier.
FIFA has been plunged into several corruption scandals this year, which played a key role in Blatter's announcement in June that he would stand down when a new election is held in February.
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Platini was considered favourite to take over but his campaign has been frozen since he and Blatter were suspended in October over the payment which they insist was legal.
The United States asked Switzerland to freeze about 50 accounts in Swiss banks linked to its massive inquiry into football corruption, the Tages Anzeiger newspaper reported.
The newspaper said the action involved about 50 accounts in 10 Swiss banks. Numerous FIFA members are known to have accounts in the country.
Nicolas Leoz, a longtime head of the South American confederation, CONMEBOL, had 12 accounts in Switzerland, the newspaper said quoting details from the US request.
The United States has charged 39 individuals, including Leoz, and two companies over bribes of more than USD 200 million paid for football marketing and television rights deals.