South Korea’s quest to become a middle power, articulated through autonomy in foreign policy, has been challenged in the ambience of great power competition reality between the USA and China. This article delineates South Korean foreign policy’s complex nature in the evolving East Asian regional context, focusing on Seoul’s relationship with China in particular. Many observers noted that South Korea has in recent years been increasingly leaning towards China, despite the fact that it is a military-pact ally of the USA. It also comes as a bewilderment to outsiders to notice that South Korea has been ‘cold-shouldering’ Japan, the world’s number three economy. It does not necessarily mean that Seoul maintains good relations with China either. The two nations have yet to overcome the Terminal High Altitude Area Defense (THAAD) dispute. This article also scrutinises how the USA plays an important role in South Korea’s relations with its two neighbours. Seoul has been in search of diplomatic autonomy between the world’s two most powerful nations. The process has been tumultuous. The future outlook seems uncertain.