The 35-year-old pilot was flying a Swedish-made JAS 39 Gripen jet.
Thailand’s national Children’s Day is celebrated yearly on the second Saturday of January.
Footage of the accident captured shrieks from a startled crowd as the jet took a nosedive and crashed near the airport’s runway, releasing fiery plumes of smoke.
“One pilot was killed in the accident this morning,” defence ministry spokesman Major General Kongcheep Tantravanich told AFP.
No one else was harmed in the incident, according to an airport official, as the audience was gathered a considerable distance away from the crash site.