One train derailed in the incident, which took place just before 1pm local time (12pm GMT).
Police said the person who died was a woman, while 22 others, including three children, were hurt.
Some have been rushed to hospital for treatment, including the youngsters.
Investigators said the trains collided side by side, senfding several carriages off the railway line.
Photos from the scene showed one of the trains with its side ripped open by the impact.
Train operator OBB said a regional train and Eurocity service collided at the station “for unknown reasons”.
A spokesman said: “Due to the accident, several people were seriously injured, according to the first information from the rescuers and rescue teams.
“A traveller could be pulled free, but according to initial information, they were dead.
“All necessary rescue and rescue teams are currently on site to evacuate and look after the affected people at the scene of the accident.”
Around 20 emergency service vehicles were dispatched to the scene including fire crews and ambulances.
Some of those passengers involved had been travelling on the EuroCity service from Graz to Saarbrücken in Germany.
More to follow.