The Goguryeo–Wei War, fought in the early 3rd century CE, was a significant conflict between the Kingdom of Goguryeo, one of the Three Kingdoms of Korea, and the state of Cao Wei, one of the contending powers during the Three Kingdoms period in China. This war is notable for its context within the larger power struggles of the era and its implications for the relationships between the states in Northeast Asia.

The conflict originated from Cao Wei's expansionist policies and Goguryeo's strategic location and growing power in the Korean Peninsula, which posed a potential threat to Cao Wei's interests in the region. Cao Wei, under the leadership of its ambitious rulers and generals, sought to assert its dominance and extend its influence over the Korean Peninsula, which included the territory controlled by Goguryeo.

The Goguryeo–Wei War was marked by a series of military campaigns and battles. The most significant of these was the campaign led by the Wei general, Cao Cao's son Cao Zhen, and later by Sima Yi, one of Wei's most prominent military strategists. These campaigns were aimed at subjugating Goguryeo and bringing it under Wei control.

The terrain of the Korean Peninsula, particularly the mountainous regions and the fortifications of Goguryeo, posed significant challenges to the invading Wei forces. Goguryeo, under the reign of its king, Gwanggaeto the Great, had developed strong defensive capabilities and a formidable military. The kingdom was well-prepared for the conflict, having anticipated Wei's expansionist ambitions.

One of the most notable aspects of the war was the Siege of Goguryeo's capital, Pyeongyang. This siege demonstrated the tenacity and resilience of the Goguryeo defenders, as well as the logistical challenges and limitations faced by the Wei forces in sustaining a prolonged military campaign far from their base.

Despite initial successes, Wei's campaigns ultimately did not succeed in conquering Goguryeo. The difficulties in maintaining supply lines, the fierce resistance by Goguryeo, and the challenging terrain all contributed to Wei's inability to secure a decisive victory. The failure of these campaigns highlighted the limits of Wei's military reach and the emerging power of Goguryeo as a regional force.

The Goguryeo–Wei War had significant implications for the power dynamics in Northeast Asia. It prevented Wei from extending its influence over the Korean Peninsula and solidified Goguryeo's status as a major power in the region. The conflict also drained resources and attention from Wei, which was already engaged in ongoing struggles with the other two kingdoms of Shu Han and Wu in China.