The nine uniforms and two silver helmets of the Life Guards and Blues And Royals regiments of the Household Cavalry were taken during a break-in in Haringey, north London, a fortnight ago.
The striking garments, worth more than £60,000, are those worn by the senior army units when they undertake ceremonial roles including Trooping the Colour at Horse Guard's Parade on the Queen's official birthday, and the State Opening of Parliament.
The Duke of Cambridge and Prince Harry were both commissioned into the Household Cavalry's Blues And Royals when they graduated from Sandhurst.
The Metropolitan Police said that the burglary took place at 5.50pm on August 18.
A spokesman said: "The combined value of these items is in excess of £60,000."