The 32-year-old will make his first appearance in a downtown court around 1:00 pm (1100 GMT), for arraignment over Friday's bombing and shooting spree that he said he had planned over a long time and executed singlehandedly.
The key initial decision to be taken by the judge is whether to order the hearing staged behind closed doors.
Behring Breivik, said to be linked to far-right groups, wants a public hearing and explain why he staged the attacks, his lawyer said.
"He has two wishes: the first is that the hearing is public, and the second is that he may attend in uniform," Geir Lippestad told broadcasters NRK.
Before the attack, Behring Breivik wrote a 1,500 page manifesto, datelined London, in which he claimed his mentor was an Englishman called Richard, The Daily Telegraph reported Monday.
He boasted that he was one of up to 80 "solo martyr cells" recruited across Western Europe to topple governments tolerant of Islam, it said, adding that Scotland Yard was now trying to establish if he had visited London in recent years.
At least seven people died in an initial blast outside the prime minister's office, in a calculated distraction for police allowing Behring Breivik to shoot 86 more -- mainly youths on the island of Utoeya, 40 kilometres away (25 miles).
Others remain unaccounted.