Portland Place is a street in the Marylebone district of central London, England.

The street was laid out by the brothers Robert and James Adam for the Duke of Portland in the late 18th century and originally ran north from the gardens of a detached mansion called Foley House. It was said that the width of the street was conditioned by the Duke's obligation to his tenant, Lord Foley, that his views to the north would not be interfered with.

In the early 19th century Portland Place was incorporated into the royal route from Carlton House to Regent's Park developed for the Prince Regent by John Nash. The street is unusually wide for central London (33 metres / 110 feet). It still contains many of the spacious Georgian terraced houses built by the Adams, as well as some early 20th century buildings and a few post World War II bombing infills.

In administrative terms, Portland Place lies within the City of Westminster's Marylebone High Street Ward as well as the Harley Street Conservation Area.