The queue for entry stretched across the square as more than 3,000 people arrived, according to Heute.
Annabella Khom, one of the organizers of the event, said that job offers had already been made at the fair.
The organizers said in a statement: "Integration must happen in the job market. It is important to create new perspectives for businesses as well as for refugees."
Businesses involved included large brands Spar, T-Mobile and Rewe as well as many others from the trade, technology, tourism and charity sectors. A Spar personnel manager told Heute she was "enthusiastic" about several of the interviewees, and that the company needs to take on 400 new employees by the end of the year, after market changes due to the bankruptcy of the Zielpunkt supermarket chain.
As well as finding information about employment, there were also workshops offering advice on job applications, a free photo booth and talks from refugees working in Austria.
Back in April, a jobs platform for refugees, Refugees Work, was launched. 140 companies and 1,000 refugees signed up in just the first few days, and one of the founders told The Local: "Employers want to hire new people and they know that many refugees are trained and were even heading up companies in their home countries."
Last year, 90,000 asylum applications were registered in Austria, but finding employment can be difficult for new arrivals. The law in Austria states that people going through the asylum process are legally not allowed to be in paid work.
Those who do receive refugee status - which can take years - have the same access to the labour market as everybody else, although the perception of some employers that it is complicated or sometimes unattractive to hire refugees, which can make it more difficult to get work.