Ki Chul Koh, 50, the president and founder of Koh Management and Computer Systems, Inc., in Rockville and a former officer in the Republic of Korea army, was killed Monay in a traffic accident in Roanoke.

Virginia State Police said the car in which Mr. Koh was a passenger was attempting to turn off a highway when it was struck from behind by a tractor-trailer. The vehicle was crushed between the tractor-trailer end a guardrail. Police said Kenneth Thomas Toth, an official of Mr. Koh's firm, also was killed and that the driver of their car was injured.

Mr. Koh, who was born in Korea, graduated from Chosun University and earned a master's degree in public administration from Seoul National University. He was a lieutenant colonel in the army of the Republic of Korea in 1964, when he resigned his commission and came to the United States.

He settled in the Washington area and worked for a number of computer firms. He also attended Howard and American universities. He founded his own company in 1979. He lived in Potomac.

Mr. Koh was a senior elder at the Korean Church of WAshington.

Survivors include his wife, Yong-Soo Koh, a daughter, Hee-Jung Koh, and a son, Tommy, all of Potomac.