I'm currently holding Vietnamese passport and studying in Australia. I read some sources saying that I don't have to apply for visa if I already have a valid Australia visa. Is that true? Or will I be granted a visa on arrival or just buy a ticket and then go?
According to Timatic you may not need to if you don't depart back to Australia when arriving from Australia.
Visa required, except for Holders of a visa issued by Australia, Canada, Japan, New Zealand or USA to nationals of Viet Nam, only if in transit through Korea (Rep.):
For details, click here
Holders of a visa issued by Australia, Canada, Japan, New Zealand or USA to nationals of any country except for Cuba, Iran, Macedonia (FYROM), Sudan and Syria, only if in transit through Korea (Rep.):
holding confirmed onward tickets on flights departing within 30 days; when
arriving from a third country, departing to the country that issued the visa (e.g. DEL-ICN-YVR); or
arriving on a direct flight from the country that issued the visa (a visa that expired on departure from that country is accepted), departing to a third country (e.g. YVR-ICN-DEL).
Not applicable to holders a group visa issued by Japan or an e-visa.
Not applicable if traveling from/to Guam or Northern Mariana Isl.
Visa required, except for A max. stay of 30 days for nationals of Viet Nam traveling as tourist, if arriving at and departing from Jeju (CJU) and For details, click here
Visa required, except for Holders of an APEC Business Travel Card (ABTC)For details, click here provided endorsed Valid for travel to KOR".
Visa required, except for Those who have previously entered Korea (Rep.) at least 4 times within the last 2 years, or at least 10 visits in total.
- Nationals of Viet Nam traveling as a group on business or as a group of school children can be issued with a Group Visa.
- Holders of e-visas are required to hold an Electronic Visa Issuance Confirmation, issued by the Ministry of Justice.
- Visitors are required to hold proof of sufficient funds to cover their stay and documents required for their next destination.
- Passport number and nationality must match those stated on the APEC Business Travel Card (ABTC).
Long story short you will need a visa for a trip: (Australia) -> Korea -> (Australia) otherwise if you add Viet Nam into the trip either as a source or as a destination you may not need a visa if departure from Korea is within 30 days of your arrival.