Lim, Hyung-soo Hongsan (鴻山) battle was a combat which General Choi Young (崔瑩) defeated Japanese pirates (倭寇) who invaded Geum River (錦江) basin at the Hongsan region in July 1376 (2nd year of King Woo, 禑王), which is considered as one of great military victories over the course of 40-year fight against Japanese Pirates. The battle is worthy of special mention and is also assessed as a ‘Sweeping Victory (大捷).’This study briefly summarizes the background and process of development happened in Hongsan Battle and reviewes wether the battle could be really assessed as a ‘Sweeping Victory’ or not and wether the Taebong Mountain Fortress (胎峰山城) could be considered as valid battlefield. This study pointed out that Hongsan Battle somewhat falls short of being assessed as a Sweeping Victory (大捷) in that not only the scale of military force mobilized and military accomplishments gained during the battle are unclear but also the battle did not have any significant effects on the features of the war even after the battle. And yet, the study evaluated that Hongsan Battle still holds significant historical meaning of its own in that it lived up to desperate requirements of the time to a certain degree even though it did not make accomplishments enough to satisfy expectations. The study then examined if the recognition that the battlefield of Hongsan was Taebong Mountain Fortress is correct. This recognition was the result of establishment of Hongsan Memorial Stone (鴻山大捷碑) in the process of designating Taebong Mountain Fortress as one of the remains of historical national protection in the late 1970s, which was a hasty outcome without the support of documentary records or excavation survey. Thus, careful comparison of geographical conditions with historical records of Hongsan Battle reveals considerable discrepancies. Although it is very difficult to assert any specific region as the battlefield of Hongsan Battle given the lack of related data available, as the result of assumption based on geographical characteristics which appeared in the historical data, there is high possibility that the battlefield was actually valleys around Bihong Mountain(飛鴻山).