Guardsman Charanpreet Singh Lall marched among 1,000 British soldiers who took part in the Trooping the Colour parade.
His turban was black, matching his comrades' headgear and featured the Coldstream Guards' ceremonial cap star.
"Being the first turban-wearing Sikh to troop the colour and to be part of the escort is a really high honour for me and hopefully for everyone else as well," said Mr Lall from Leicester, who came to the UK from India as a boy.
"I'm quite proud and I know that a lot of other people are proud of me as well," he was quoted as saying by the BBC.
Mr Lall said he expected it would encourage those from different religions and backgrounds to join the Army.
"I hope that people watching will just acknowledge it and look at it as a new change in history," he said.
Prince Harry and his wife Meghan Markle also joined other senior royals at the event.
It was the first time Meghan Markle had attended the ceremony following her marriage to Prince Harry on May 19.
While 92-year-old Queen Elizabeth II celebrated her actual birthday on April 21,the Trooping of the Colour ceremony takes place on any Saturday of June.
The ceremony has commemorated the birthday of the sovereign for more than 250 years and also functions as a display of army drills, music and horsemanship.