Six police vehicles attended the scene, according to a report from the Austrian Press Agency (APA).
Police were alerted after an anonymous call to Austrian national railways (ÖBB). Several platforms at the main station were closed and passengers were also asked to evacuate the Meidling underground line station.
No explosives were found and the all-clear was given at 11:17 pm.
Earlier in February, another bomb threat forced the closure of the Handelskai U6 station, while police investigated.
The day before, police arrested a 26-year-old man suspected of making at least ten hoax bomb threat calls.