Prison guards brought Habre, dressed in a white robe and turban, into the special court in the capital Dakar, an AFP reporter saw.
Habre, once dubbed “Africa’s Pinochet”, refused to speak and the court appointed three attorneys to defend him.
The trial, seen as a test case for African justice, had opened on Monday, a quarter of a century after his reign came to an end.
Habre, accused of war crimes, crimes against humanity and torture, had refused legal representation, saying he did not recognise the court’s jurisdiction and vowed not to cooperate with the trial.
The court appointed three lawyers to assist him and then adjourned the trial until September 7 to give them time to prepare their defence.
Habre then rose and gave a clenched-fist salute and V-for-victory sign to his supporters, who shouted “Allah akbar” (God is greatest).
Habre — backed during his presidency by France and the United States as a bulwark against Libya’s Moamer Kadhafi — is on trial over actions under his regime from 1982 until he was ousted in 1990.
Rights groups say 40,000 Chadians were killed under Habre’s regime.
The former president, 72, has been in custody in Dakar since his arrest in June 2013 at the home he shared in an affluent suburb of the Senegalese capital with his wife and children.