| Unit Name: | 4th Marine Battalion |
| Dates: | 1961–1975 |
| Branch: | Republic of Vietnam Marine Division |
| Type: | Marines |
| Role: | Amphibious warfare Anti-tank warfare Artillery observer Close combat Counterinsurgency Force protection Jungle warfare Raiding Reconnaissance Urban warfare |
| Size: | Battalion |
| Garrison: | Hoang Hoa Tram camp |
| Nickname: | "Killer Sharks" |
| Battles: | Vietnam War |
| Commander1: | Captain Bui The Lan |
| Commander1 Label: | Battalion Commander |
| Commander2: | Captain Nguyen Van Nho |
| Commander2 Label: | Vice Battlaion Commander |
| Commander3: | Lieutenant Nguyen Thanh Tri |
| Commander3 Label: | Captain of 1st Company |
| Commander4: | Lieutenant Tran Van Hoán |
| Commander4 Label: | Captain of 2nd Company |
| Commander5: | Lieutenant Nhat |
| Commander5 Label: | Captain of 3rd Company |
| Commander6: | Lieutenant Ton |
| Commander6 Label: | Captain of 4th Company |
The 4th Marine Battalion was a infantry marines battalion falling under command the 147th Marine Brigade during the Vietnam War. The battalion was formed in early 1961 and based at Vũng Tàu in Phước Tuy province (now Bà Rịa–Vũng Tàu province). On 30–31 December 1964, it was ambushed by elements of the Viet Cong 9th Division near the Quang Giao rubber plantation, 4km (02miles) south east of Bình Giã and suffered 60% casualties. The battalion ceased to exist after the Fall of Saigon on 30 April 1975 and the collapse of the South Vietnamese government.