Austria is part of the Schengen area. EU nationals and citizens of other members of the Schengen area do not need a visa, but a passport or valid ID card is required.
Citizens of states outside the Schengen area might need a visa, which can take up to several weeks to process.
For information on visa requirements please check this homepage of the Austrian Foreign ministry and consult your local Austrian embassy or consulate.
FAQs for Ukranian students and scientists: Austrian Ministry for Inner Affairs