The court trying Brotherhood leader Mohammed Badie and five other members of the Islamist group postponed hearings until October 29.
The defendants, two of whom are being tried in absentia, are accused in relation to clashes outside the group's Cairo headquarters on June 30 that left nine people dead.
At another courtroom in eastern Cairo, Mubarak looked relaxed in his first court appearance since he was released from prison last week and transferred to a military hospital. The 85-year-old ex-president, whose lawyer has claimed has been on the verge of death, sat in a chair next to his two sons who are being tried in a separate corruption-related case.
Mubarak has been in detention since April 2011, two months after he was ousted in an uprising against his rule.
He was found guilty and sentenced to life in prison last year for failing to stop the killing of some 900 protesters in the uprising, but his sentence was overturned on appeal.
In April, his retrial opened along with those of his security chief and six top police commanders.
His trial was postponed to September 14.