London fog may refer to:

• London Fog (nightclub), a 1960s nightclub on the Sunset Strip where The Doors first played as a house band.
• London fog, the so-called "pea-soup fog" in London in the late 19th and early 20th centuries: see Pea soup fog or Great Smog of 1952.
• London Fog (beverage), a hot beverage consisting of steamed milk, vanilla syrup and Earl Grey Tea.
• London Fog (cocktail), an alcoholic drink made with gin and Pernod.
• London Fog (company), a popular manufacturer of coats and other clothes