State news agency MENA said that Badie, 71, and 13 top Brotherhood members were found guilty of “plotting attacks aimed at sowing chaos” in Egypt in 2013.
They were accused of setting up an “operations room” to prepare attacks against the state in the weeks after the army ousted president Mohamed Morsi in July 2013.
In November that year the Brotherhood was declared a “terrorist organisation” as part of a brutal crackdown by the authorities against his supporters that left hundreds dead.
Thousands have also been jailed, often in speedy mass trials that have sparked an international outcry over the fairness of such proceedings, with UN Secretary-General Ban Ki-moon expressing his alarm.
MENA said among Badie’s co-defendants sentenced to death were the Brotherhood’s former spokesperson Mahmud Ghazlan, former provincial governors and other senior members of the outlawed group.
Defence lawyer Ahmad Helmi branded the verdicts as “farcical”, said in a telephone interview.
He said the verdicts were handed down even though the defence had not finished its closing arguments concerning five of the defendants.
MENA said the court had referred its verdict to Al-Azhar, the country’s top Sunni Muslim authority, for an advisory opinion in accordance with Egyptian law before ratifying the death sentences.
Al-Azhar’s opinion is not binding with the court having the final say in the case, and could choose to commute the sentence which can later be challenged in an appeals court.
A total of 51 suspects, including the 14 sentenced to death Monday, are being tried in the case, 31 of whom are behind bars.
The Cairo court said it would announce the final verdict in the case on April 11.
Meanwhile a court in the northern city of Mansura also sentenced to death eight Brotherhood members accused of setting up a “terror cell” and murdering opponents of the Islamist organisation, MENA said.
Their verdicts were also referred to Al-Azhar, said the agency, adding that the court would give a final verdict in that case on June 22.
Badie has already been sentenced to four life terms in separate trials and was condemned to death for incitement to violence but that sentence was overturned and he is now facing a retrial.
Since the overthrow of Morsi the authorities have launched a brutal crackdown against his supporters, including leaders from his Muslim Brotherhood, leaving hundreds dead and thousands jailed after often speedy mass trials.
Morsi himself is facing several trials on charges that are punishable by death.
On March 7, Egypt carried out the first execution to a man involved in violent clashes two days after Morsi’s ouster.
The interior ministry said Mahmud Ramadan had thrown children from the roof of a building in the port city of Alexandria during violent clashes organised by the Brotherhood.