The Department of Foreign Affairs and Trade (DFAT) provides advice for business travellers and tourists going to Iran. This is regularly updated and should be checked before planned travel.
Australia has enforced United Nations Security Council as well as autonomously imposed sanctions that restrict a range of commercial activities within Iran as well as with Iranian individuals and entities. If you are considering commercial or other dealings with Iran we recommend that you familiarise yourself with the operation of these sanctions and obtain independent legal advice before making commercial decisions with respect to Iran.
More information on doing business in Iran