The teenager was sentenced to a year in prison by the court in Vienna, but told that she would not be asked to spend any further time in jail because she has been in custody since her arrest.
"It has been the worst time of my life. Now I just want to go home," the school girl told Swedish newspaper Dagens Nyheter just after the verdict was announced.
"I am happy that my client is free, that was the goal. My client is happy to leave Austria," added her lawyer Wolfgang Blaschitz.
The girl was tracked down by Austrian police last December to Vienna's Westbahnhof rail station, after her parents reported her missing from her home in Linköping in southern Sweden and told police they suspected she had become radicalized after watching Isis videos.
Austrian detectives said she was planning to travel from Vienna to Syria. But Blaschitz, argued his client was not guilty and suggested she ran away from home because she was "naive" and unhappy, and had no final destination in mind.
The teenager had made her way to Vienna by bus and train via Gothenburg, Malmö, Copenhagen, Hamburg and Munich. In Vienna, the suspect said she planned to meet with three girls from Somali families and was hoping to do some sight seeing in the Austrian city.
However, the Austrian prosecutor accused her of planning to travel onto Syria to join jihadist fighters.
The girl's mobile phone records formed a core part of the evidence given at the trial. They included messages such as "but if they cannot be converted, they must be killed" and texts in which she expressed happiness about the Paris terror attacks in November 2015.
Isis propaganda photos were also discovered, including images of beheadings.
The girl told DN on Thursday that she would "never save these pictures and talk to these kinds of people".
However her father suggested to the newspaper that she had been "brainwashed with ideology".
After her arrest, Sweden did not request that the schoolgirl be extradited, because under Swedish law preparing for a trip to join the jihad is not currently a criminal offence, although it is in Austria.
The girl has not been named by Swedish or Austrian media due to her age, but is understood to have been born and raised in Sweden. She was attending a high school in Skäggetorp, an area of Linköping with a growing proportion of immigrant families and higher than average unemployment.
The TT news agency reported that she would attend a youth programme designed to help her question and leave behind any radical beliefs.
Elisabeth Gustafsson, who chairs the city's social welfare committee told the TT news agency that she would also be helped by local authorities following her return to Sweden.
"Social services will give her the support and help we can give. What we wish is that she can come home as quickly as possible after this, and there is good preparation for that as well," she said.