For entering Australia it is required that citizens of all countries (New Zealand is exempted from this rule) have a valid visa no matter if you are a tourist, student, trainee, business canvasser etc.
For more information please visit the website of the Department for Immigration and Citizenship: http://www.immi.gov.au/
Overseas Students
Our overseas students travelling to Australia on a student visa can find detailed information on their visa subcategory as well as the required documents for their visa application and our enrolment procedure here.