The exercise assumed a situation that a DPRK vessel suspected of carrying weapons of mass destruction sails past the ROK's territorial waters off the southern resort island of Jeju.
It marked the first maritime exercise for a navy unit stationed at a Jeju Island port, which was launched late in February.
The ROK's navy mobilized various battleships, including a 7,600-ton Aegis-equipped destroyer, a 4,400-ton destroyer and a 400-ton guided missile patrol gunboat, a 1,200-ton submarine, a P-3 maritime patrol aircraft and a Lynx anti-submarine helicopter.
The inspection exercise for a DPRK vessel came amid the scheduled vote on Wednesday on a new UN Security Council resolution against the DPRK's recent nuclear test and rocket launch.
The new resolution reportedly includes mandatory inspection of cargo leaving and entering the DPRK.
Pyongyang tested what it claimed was its first hydrogen bomb on Jan. 6, and went ahead with the launch of a long-range rocket, which was condemned by outsiders as a test of banned missile technology, on Feb. 7.