The two defendants have been accused of recruiting and murdering for the so-called Islamic State group.
The trial against Islamic preacher Mirsad O., and co-defendant Mucharbek T., will hear from more witnesses when it resumes later this year, as well as an additional report regarding the translation of a Bosnian speech.
Mirsad O., who is also known by the Islamic name of 'Ebu Tejma' and is thought to be a major player in the radicalisation of Islam in Austria, had been arrested in November 2014 in a raid on his house in Vienna where he lived with his pregnant wife and five children.
The move was part of a series of raids in Vienna, Linz and Graz, which followed a two-year investigation into several people suspected of recruiting young people to fight in Syria.
In total, 13 suspected jihadists are being taken to court on terrorism charges. Other defendants are being tried separately on charges that include belonging to a terrorist organisation, heading up a criminal gang and making false statements during police questioning.
This case is the first time a Muslim has been charged with murder through terrorism in Austria and if found guilty Mirsad O. could face up to 20 years in prison.
The co-defendant in this trial, 28-year-old Mucharbek T, is also accused of carrying out numerous murders of civilians in Syria.
Both men plead not guilty.
The trial was hit by drama last week when one of the witness was arrested after giving evidence in court that contradicted his previous statements to police.
The witness told the court that he could not remember anything about the suspect being a preacher and even suggested that a statement he provided in 2013 had been written by police, although he later explained it was ‘his mistake'.
Another witness said that he knew Mirsad O. from the mosque by had never heard him asking people to go to Syria.
“He preached about praying, fasting and being good to your parents”, he said.