The siege of Ulsan () was an unsuccessful Ming-Joseon attempt to capture Ulsan from the Japanese. The siege lasted from 26 January to 19 February 1598.
Yang Hao, Ma Gui, and Gwon Yul met up at Gyeongju on the 26 January 1598 and marched on Ulsan with an army of 50,000.
On January 29th, Yang Hao and Ma Gui dispatched Li Rumei to Ulsan to lure the enemy. The Japanese army came out but were ambushed by cavalry, resulting in their defeat. The Ming army beheaded over 500 Japanese soldiers. In addition to beheading, the Ming army also drove away many Japanese soldiers to drown them.ï¼ÂDuring the battle on this day, the Koreans believed that Li Rumei was trying to lure , but over time, there were internal military conflicts. This achievement was given to another general named Baisai, but he actually appeared as an ambush. This is a wrongful case that has lasted for hundreds of years. ï¼Â
On January 30th, infantry launched rockets and cannons to attack the city, and the fire spread, burning down a large number of Japanese houses, food, and livestock. Taking advantage of the situation, they captured Japanese fortresses Taehwa River Fort and Seonghwangdang Togul. In addition to beheading, many Japanese soldiers were burned to death. But in the end, the Dosan Fortress was very tall and sturdy, with bullet holes as dense as a honeycomb. The Ming army could not capture it, and the cannon could not hit it because it was too tall and sturdy.
On January 31st, infantry once again attacked Dosan Fortress, suffering significant casualties.
On February 1st, Yang Hao ordered the Ming army to rest, and the Korean army came to attack Dosan Fortress, but to no avail. At night, suddenly at this time, the sky started to rain heavily.On February 2nd, the whole day was filled with wind and rain, and the army launched an attack despite the rain, but to no avail. The Ming army repelled 30 Japanese warships that came to rescue them. The Japanese attempted to negotiate peace with the Ming army, but deceived them by claiming that Kat à  Kiyomasa was not in Dosan Fortress and attempting to bring a Korean general into the Japanese camp.
On February 3rd, the army came to attack Dosan Fortress ,still no avail. The rain stopped that day, but at night, a strong wind blew up and the weather was extremely cold. The mud covered my knees, and the soldiers developed frostbite, their fingers were frozen to death. A large number of war horses starved or froze to death. The situation of the Japanese army in Dosan Fortress is also not good. The city has not been repaired, so there is no food, grass, or water source.On February 4th, the Ming army repelled 26 Japanese warships that came to rescue. At night, the Ming and Korea army came to attack Dosan Fortress, but to no avail.On February 5th, the Japanese army attempted to negotiate peace with the Ming army again, and Kat à  Kiyomasa expressed his willingness to leave the city to meet with Yang Hao. Yang Hao wants to capture Kat à  Kiyomasa alive.
On February 6rd, Korean officials tally the casualties of the Korean army. The result obtained is: 298 Korean soldiers killed, 876 wounded, and 4982 deserters.
On the morning of February 8th, Kat à  Kiyomasa did not come out. In the afternoon, Japanese reinforcements arrived by land and water, totaling approximately 13000 people. Yang Hao and Ma Gui attempted their final siege at night, but still failed.On February 9th, Yang Hao was worried about being attacked by the enemy, so he led his army to retreat and appointed Li Rumei and other cavalry generals as the rearguard. The Ming army retreated in an orderly manner and even burned down the materials that could not be taken away, resulting in no significant losses for the Ming army's main force. But the army troops responsible for blocking the Japanese from crossing the river in Jeontan suffered heavy losses. Yang Hao and Ma Gui were very disheartened. Both Ming and Korean people had high expectations for this battle, but they lost.
Joseon and Ming forces losses according to Ming sources numbered 798 killed at the battle and a further 823 dead by injuries for a total of 1,621 dead. The wounded reached 2,908.
According to Hawley, the Japanese garrison at Ulsan Castle numbered 10,000 men, with less than 1,000 surviving the siege. Two Japanese historical sources claim the Japanese garrison numbered either 20,000 or 23,000.
Yang Hao would ultimately be called back to Beijing for his failure at Ulsan on 12 August 1598.