Battle of Haeju

{{Short description|Small naval battle during the Korean War}}

{{No footnotes|date=September 2017}}

{{Infobox Military Conflict

|conflict=Battle of Haeju

|image=

|caption=

|partof=the Korean War

|date=September 10, 1950

|place=off Haeju Bay, Korea, in the Yellow Sea

|result= United Nations victory

|combatant1={{flag|United Nations}}

• {{Flagcountry|First Republic of Korea|1949|size=23px}}

|combatant2={{Flag|North Korea|1948|size=23px}}

|units1=Republic of Korea Navy

|units2=Korean People's Navy

|strength1=1 patrol boat

|strength2=1 minelayer

|casualties1=None

|casualties2=Unknown human casualties,
1 minelayer sunk

|}}

{{Naval engagements of the Korean War}}

{{Campaignbox Korean War}}

The Battle of Haeju was a small naval battle during the main phase of the Korean War.

Off Haeju Bay in the Yellow Sea, on September 10, 1950, days before the Battle of Inchon, a South Korean navy patrol boat, PC-703, encountered a North Korean navy minelayer sailing vessel. After a brief fight, the North Korean minelayer was sunk with a loss of all crew and no South Korean casualties were reported.

After the minelayer's sinking, PC-703 discovered that the sunken vessel had laid a mine field at the mouth of the Haeju Man and then reported to base the location of the sea mines. Two days later on September 12, PC-703 encountered three small transports and sank them. The three supply vessels were most likely unarmed.