I am a student in China and want to come back Uzbekistan with Shanghai-Seul(Incheon), Seul(Incheon)-Tashkent airlines and transit time is 19-20 hours do I need transit Visa of Korea? Please give me official references. Thanks
Per TIMATIC, the database used by airlines:
TWOV (Transit Without Visa): Visa required, except for Passengers transiting through Seoul (ICN) with a confirmed onward ticket for a flight to a third country within 24 hours. They must stay in the international transit area of the airport and have documents required for the next destination.
So no, you don't need a visa.