The Duke of Sussex attended his father's coronation, sitting two rows behind his brother the Prince of Wales at Westminster Abbey. The prince arrived alone without his wife Meghan, who stayed in the US, and left shortly after the ceremony.
According to the BBC, he was not invited to go out on the balcony of Buckingham Palace to greet the citizens.
It is the first time the prince has been seen at a public event with his family since the publication of his memoirs in the much-discussed book, Spare.
Prince Harry rode alone in a car shortly after the service ended.
Hours later, on the balcony of Buckingham Palace, the King and Queen were joined by other members of the royal family, including the Prince and Princess of Wales and their children.
Prince Harry's wife, the Duchess of Sussex, has been staying in Los Angeles with their children, where their son Prince Archie celebrates his fourth birthday.
A source previously told US newspaper Page Six that Prince Harry intended to make "every effort to be back in time for Archie's birthday".
Prince Harry wore a breakfast suit and medal at the ceremony and he sat with his cousin Princess Eugenie and her husband Jack Brooksbank in the third row, along with his uncle the Duke of York, Prince Andrew.
Two rows ahead at the front were the Prince and Princess of Wales and their children Princess Charlotte and Prince Louis, as well as the Duke and Duchess of Edinburgh.
For the late Queen Elizabeth's funeral last year, Prince Harry was in the second row directly behind the King at the abbey. It was already known that Prince Harry would attend the ceremony alone and would not have any official role as he is not a member of the royal family.