The South Korean Defense Ministry said the US B-1B bomber was part of the bombing drills, Anadolu reported.
It is the first time in seven years that the US bomber has joined such military exercises in South Korea, the Seoul-based Yonhap News reported.
The bomber dropped "joint direct attack munitions at an unspecified location in the country, while being escorted by South Korean F-15K fighter jets," said the ministry.
The US has some 28,500 soldiers deployed in South Korea, along with arms and weaponry.
The drills by the US bomber come amid heightened tensions on the Korean Peninsula as South Korea has decided to resume all military activities along the border with North.
Pyongyang had sent hundreds of balloons carrying trash to South Korea, triggering condemnation, as well as Seoul’s move to end the 2018 pact which aims to reduce tensions with North Korea.
The North Korean leader has personally directed test military drills, stressing the need to protect the country's sovereignty.
SD/PR