The 7,600-ton KDX-III destroyer was put into service on Wednesday, after nine months of test operations, and assigned to the Navy's 7th fleet, Navy officials said.
The new destroyer was named after one of Korea's most prominent Confucian scholars, Yulgok Yi I (1536-1584).
"The Yulgok Yi I will carry out its mission of anti-air and anti-ship defense in waters on three sides of the Korean Peninsula," a Navy official said.
South Korea has built three Aegis destroyers since 2004 under a Navy buildup project, code-named "KDX-III," to bolster defense against North Korea. The first ship was commissioned in 2008, and the third ship was launched early this year.
The Yulgok Yi I Aegis destroyer (Yonhap file photo)
The 166-meter-long KDX III destroyer can carry about 120 missiles and torpedoes in its vertical launch system. With 300 crew members, it can also carry two mid-sized helicopters and sail at a top speed of 30 knots within a range of 1,000 kilometers, Navy officials said.
Inter-Korean tensions persist after North Korea sank the South's Cheonan warship near the Yellow Sea border in March last year, killing 46 sailors. Eight months later, the North bombarded the frontline South Korean island of Yeonpyeong, killing two marines and two civilians.