I'm currently holding Indonesian passport who has a Permanent Residency of Australia. I'm planning to go to Inchon and Jeju island for 1 week from Indonesia.
My question is, do I need to apply for a Korean visa?
Yes, you will need a visa, unless you travel directly to Jeju.
There is a list of countries which don't need a visa to travel to South Korea, Indonesia is not among them.
However, there are special rules when it comes to Jeju. You don't need a visa (Indonesia is not on the short list of countries which are excluded from this) if you intend to go to Jeju and take an international flight directly to Jeju. This won't allow you to go to Incheon though.
