Regent Street is one of the major shopping streets in London's West End, well known to tourists and Londoners alike, and famous for its Christmas illuminations. It is named after the Prince Regent (later George IV), and is commonly associated with the architect John Nash, whose street layout survives, although all his original buildings except All Souls Church have since been replaced.

The street was completed in 1825 and was an early example of town planning in England, cutting through the 17th and 18th century street pattern through which it passes. It runs from the Regent's residence at Carlton House in St James's at the southern end, through Piccadilly Circus and Oxford Circus, to All Souls Church. From there Langham Place and Portland Place continue the route to Regent's Park.

Every building in Regent Street is protected as a Listed Building, at least Grade II status, and together they form the Regent Street Conservation Area.

The street is one of the locations on the standard UK version of the Monopoly board game, and it is referred to in the 1966 song Dedicated Follower of Fashion by The Kinks.