The 16-year-old native Chechen from Salzburg and the 18-year-old Bosnian from Upper Austria tried to travel to Syria last December to become brides of Islamic State (Isis) fighters.
The two girls met on the internet after becoming radicalised by Isis propaganda they found online.
The 16-year-old actually married an Isis fighter from Tunisia in a ceremony carried out via an online phone call. Prosecutors say that the 18-year-old planned to marry an Isis fighter once she arrived in Syria, in order to give him moral support.
Both girls took off their veils so they would not attract attention as they began their journey from Austria to Syria by train.
However, the family of the Chechen girl became worried when their daughter disappeared and notified police. The girls were stopped by border police on the Hungarian Serbian border and held in police custody for three days. Since their release they have been cared for by youth welfare officers.
Two girls from Styria will appear as witnesses in court on Friday – after recently receiving 12 and 14 month probationary sentences after they planned to join Isis jihadists.
Membership of a terrorist organisation carries a prison sentence of between one and ten years.