I Sunsin and Won Gyun arrived near Okpo on 16 June and a scouting vessel alerted them to the presence of Japanese ships anchored there.
I Sunsin's fleet approached Okpo on 17 June. They formed battle positions with the heavy warships in the center and light vessels to the left and right. When they entered the harbor they found more than 50 transport ships, mostly unmanned, and the Japanese looting in the village. The Japanese didn't notice them until it was too late due to smoke around Okpo and panicked. Some fled into the hills whiles others tried to flee aboard their ships, but those that did were surrounded and hemmed into the port. The Japanese tried to fight back with their firearms but did little damage to the battleships. I Sunsin proceeded to bombard them until they abandoned ship. In total 26 transports were destroyed during the bombardment. The Koreans suffered three injuries, and two of them were from friendly fire. When a group of I Sunsin's men seized a Japanese ship, Won Gyun's ships fired on them, mistaking them for enemies.
After the battle Yi Sunsin immediately received news of five other Japanese ships within their vicinity and gave chase. The Japanese fled to Happo harbor and abandoned their ships.
The next day they received news of another 13 Japanese ships nearby and found them at Jeokjinpo. The Japanese fled inland while their ships were looted and then burned.
When they received news of the fall of Hanseong, I Sunsin and Won Gyun parted ways and returned to their home ports. I Sunsin arrived back at Yeosu on 18 June.
Alagappa, Muthiah (2003), Asian Security Order: Instrumental and Normative Features, Stanford University Press, ISBN0-8047-4629-X
Arano, Yasunori (2005), The Formation of a Japanocentric World Order, International Journal of Asian Studies
Brown, Delmer M. (1948), "The Impact of Firearms on Japanese Warfare, 1543–1598", The Far Eastern Quarterly May 1948 (Volume 7, Number 3: pp. 236–53), Association for Asian Studies
Eikenberry, Karl W. (1988), "The Imjin War", Military Review 68:2: 74–82
Ha, Tae-hung; Sohn, Pow-key (1977), 'Nanjung Ilgi: War Diary of Admiral Yi Sun-sin, Yonsei University Press, ISBN89-7141-018-3
Haboush, JaHyun Kim (2016), The Great East Asian War and the Birth of the Korean Nation
Hawley, Samuel (2005), The Imjin War, The Royal Asiatic Society, Korea Branch/UC Berkeley Press, ISBN89-954424-2-5
Jang, Pyun-soon (1998), Noon-eu-ro Bo-nen Han-gook-yauk-sa 5: Gor-yeo Si-dae (눈으로 보는 한국역사 5: 고려시대), Park Doo-ui, Bae Keum-ram, Yi Sang-mi, Kim Ho-hyun, Kim Pyung-sook, et al., Joog-ang Gyo-yook-yaun-goo-won. 1998-10-30. Seoul, Korea.
Kim, Ki-chung (1999), "Resistance, Abduction, and Survival: The Documentary Literature of the Imjin War (1592–8)", Korean Culture 20:3 (Fall 1999): 20–29
Kim, Yung-sik (1998), "Problems and Possibilities in the Study of the History of Korean Science", Osiris, 2nd Series, Vol. 13, Beyond Joseph Needham: Science, Technology, and Medicine in East and Southeast Asia: 48–79. JSTOR
桑田忠親 [Kuwata, Tadachika], ed., 舊參謀本部編纂, [Kyu Sanbo Honbu], 朝鮮の役 [Chousen no Eki] (日本の戰史 [Nihon no Senshi] Vol. 5), 1965.
Neves, Jaime Ramalhete (1994), "The Portuguese in the Im-Jim War?", Review of Culture 18 (1994): 20–24
Niderost, Eric (2001), "Turtleboat Destiny: The Imjin War and Yi Sun Shin", Military Heritage 2:6 (June 2001): 50–59, 89
Niderost, Eric (2002), "The Miracle at Myongnyang, 1597", Osprey Military Journal 4:1 (January 2002): 44–50
Park, Yune-hee (1973), Admiral Yi Sun-shin and His Turtleboat Armada: A Comprehensive Account of the Resistance of Korea to the 16th Century Japanese Invasion, Shinsaeng Press
Rockstein, Edward D. (1993), Strategic And Operational Aspects of Japan's Invasions of Korea 1592–1598 1993-6-18, Naval War College
Strauss, Barry (2005), "Korea's Legendary Admiral", MHQ: The Quarterly Journal of Military History Summer 2005 (Volume 17, Number 4: 52–61
Swope, Kenneth M. (2006), "Beyond Turtleboats: Siege Accounts from Hideyoshi's Second Invasion of Korea, 1597–1598", Sungkyun Journal of East Asian Studies (Vol. 6, No. 2. 2006 Academy of East Asian Studies.: 177–206
Swope, Kenneth M. (2005), "Crouching Tigers, Secret Weapons: Military Technology Employed During the Sino-Japanese-Korean War, 1592–1598", The Journal of Military History: 69, 11–42. Society for Military History
Swope, Kenneth M. (2002), "Deceit, Disguise, and Dependence: China, Japan, and the Future of the Tributary System, 1592–1596", The International History Review' XXIV. 4: December 2002: 757–1008
Swope, Kenneth M. (2009), A Dragon's Head and a Serpent's Tail: Ming China and the First Great East Asian War, 1592–1598, University of Oklahoma Press
Turnbull, Stephen (2002), Samurai Invasion: Japan's Korean War 1592–98, Cassell & Co, ISBN0-304-35948-3
Turnbull, Stephen (2008), The Samurai Invasion of Korea 1592-98, Osprey Publishing Ltd