Kaimkillenbun is an Australian town 24 kilometres (15 mi) from Dalby, on the way to the Bunya Mountains. It is in the local government area of the Western Downs Region. At the 2011 census, Kaimkillenbun and the surrounding area had a population of 566.
It is recognised as the Queensland town with the longest single name, but is affectionately known by locals as "The Bun".
Kaimkillenbun was the setting for the Nicole Kidman movie Chase Through the Night and it was also the birthplace of Olympic basketballer John Dorge.
Facilities in the town include the historic Bun Pub, a primary school and a number of sporting clubs and organisations.
Kaimkillenbun Post Office opened by June 1909 (a receiving office had been open from 1908).