"We purchased this airplane in March 2006. Currently we understand that there are no engine or mechanical problems," Yoon Young-Doo told a press conference, adding that the two people killed were Chinese nationals.
South Korea's transport ministry said separately both the dead were female, born in 1996 and 1997.
The ministry said the plane's tail hit the runway and the aircraft veered to the left off the runway. A total of 181 people were injured.
Yoon said the crew had made an in-flight broadcast as usual, "asking passengers to buckle up for landing. There was no emergency alarm".
He said one pilot had more than 10,000 flying hours, and the other more than 9,000.
"Our pilots strictly comply with aviation rules," the CEO said.
He said the two people who died were passengers seated at the back of the plane.