About 160 people are said to have died in attacks since May 2003
A court in Saudi Arabia has issued verdicts, prosecutors say, in what is thought to be the first terrorism trial for al-Qaeda militants in the kingdom.
Justice ministry officials say 330 had been on trial, but they did not specify how many had been found guilty. One defendant was given a death sentence.
Al-Qaeda-linked militants launched a violent campaign to destabilise the absolute monarchy in 2003.
The authorities launched an aggressive campaign to stamp it out.
"A specialised criminal court has recently issued several preliminary verdicts in cases of defendants in al-Qaeda and state security terrorism crimes," said a statement from the Bureau of Investigation and General Prosecution, carried by the official Saudi Press Agency.
The defendants can appeal.
A spokesman quoted by AP news agency said the defendants had faced charges of belonging to "the deviant group", used to denote al-Qaeda.
They were accused of supporting and financing terrorism, going to areas of conflict to fight, and conspiracy to create chaos and disrupt security, he said.
The charges came with "incriminating evidence... and proof that every defendant has carried out the charges against him", he added.
Last October, Saudi Interior Minister Nayef bin Abdul Aziz announced that charges had been laid against 991 suspected al-Qaeda militants.
Analysts said until then the government had been reluctant to try suspected militants, fearing a backlash by domestic sympathisers.
Militants had been responsible for more than 30 attacks in the conservative Muslim kingdom since May 2003, and the authorities claimed to have foiled 160 planned attacks.
Officials figures say 90 civilians and 74 members of the security forces have been killed, while 439 civilians and 657 members of the security forces had been injured.