Chris Edgerley, a senior scenes of crime officer (SOCO) for Thames Valley Police in Slough, is retiring on Tuesday, June 5, the day of the Queen's Diamond Jubilee.
His boat, La Chemme, will be one of the 1,000 boats sailing on the River Thames as part of the pageant on Sunday, June 3.
He said: "It will be amazing celebrating my retirement with millions of people across the world who will be watching the Pageant."
Mr Edgerley applied to take part in the event, which will include a mix of boats as well as music, fireworks and special effects, and was notified in December 2011 that his application had been successful.
In July, Mr Edgerley is also volunteering at Dorney Lake for the Olympic Anti-Doping Department, and will act as a chaperone for athletes being drugs-tested.
Starting work as a police cadet in 1968, Mr Edgerley, who grew up in High Wycombe, started working as a scenes of crime officer in 1975, working in Amersham and Maidenhead before moving to Slough as a senior officer in 2002.
He said the crime scene that will always stick with him was his work as part of the team that carried out post-mortems following the Hungerford Massacre in 1987, in which 16 people were killed.
He added: "It will never cease to amaze me what people will do to people and the things I have had to deal with on a daily basis."
During the Windsor Free Festival in 1974, he was injured when he was hit in the head with a tin while trying to break up the festival.
Mr Edgerley and his wife Suzy, who currently live in Maidenhead and have two grown-up children, own a cottage in Dorset where they are both planning to retire to this year.