The Palace of the People (Palatul Poporului) in Bucharest, Romania is reputed to be the world's second largest building (after The Pentagon), measuring 270m by 240m, 86m high, and 92m under ground. It is 12 stories tall, and has four additional underground levels.

Built on the site of a hill variously know as Spirei Hill, Uranus Hill, or Arsenal Hill, which was razed for the project, the building anchors the west end of Unirii Boulevard and the Centru Civic. Construction began in 1984. The building was originally to be known as the House of the Republic (Casa Republicii) and was intended to serve as a palace for Nicolae Ceauşescu. However, the project was just nearing completion at the time of his 1989 overthrow and execution.

Officially renamed first as the House of the People (Casa Poporului) and later as the Palace of Parliament (Palatul Parliamentului), the building is most commonly referred to by Bucharesteans as the Palace of the People (Palatul Poporului). It is also, not uncommonly, known as the Madman's House (Casa Nebunului).

The building is constructed entirely of materials of Romanian origin; it is reported that during the latter years of construction, this building and the Centru Civic in general created such a massive demand for Romanian marble that tombstones throughout the country had to be made from other materials.

Since 1994, the building has housed Romania's parliament; it also contains a massive array of miscellaneous conference halls, salons, etc., used for a wide variety of other purposes.