John Lawrence Gildner, 66, a retired Air Force colonel and hospital administrator who had been chief executive officer for 20 years of the Regional Institute for Children and Adolescents in Rockville, died of cancer Nov. 3 at his Seabrook home.

A former administrator of the hospital at Andrews Air Force Base, he had lived in the Washington area for 30 years. He was the founding administrator of the Rockville facility, which treats emotionally disturbed children.

Mr. Gildner was born in Austin, Minn. He was a graduate of the University of Minnesota, where he also received a master's degree in hospital administration. He served in the Air Force for 26 years in France, Germany, Labrador and elsewhere.

He received a Legion of Merit, an Award for Distinguished Service to Education from the Montgomery County Board of Education and an award from the Association of Military Surgeons for outstanding accomplishments in federal health care management. His hobby was watercolor painting.

He was a fellow of the American College of Hospital Administrators and a member of the Federal Health Care Executives Institute, Washington Society of Landscape Artists, Association of Mental Health Administrators and Glenn Dale United Methodist Church.

Survivors include his wife of 44 years, Carol S. Gildner of Seabrook; two sons, Gregory L. Gildner of Venice, Fla., and Scott B. Gildner of Scottsdale, Ariz.; two brothers, Jay W. Gildner of Chevy Chase and Van H. Gildner of Boulder City, Nev.; a sister, Mary E. Snore of Naples; and four grandchildren.