Guardian may refer to:

• A legal guardian, a person responsible for a ward.
• Guardian, one of the four temperaments according to the Keirsey Temperament Sorter.
• The Guardian, a British newspaper.
• Guardian, a New York newspaper, published as the National Guardian from 1948 to 1967 and Guardian from 1967 to 1992.
• The Guardian , a CBS TV show.
• Guardian, a Marvel Comics superhero and a Silver Age DC Comics hero.
• Guardian, the final villain of the Ultima series.
• Guardian , a contemporary Christian rock band.
• Guardian , a Bigelow Aerospace space station module.
• An operating system used on computers made by Tandem Computers, now HP.
• HMS Guardian, three ships of the Royal Navy.