The Forbidden City (Chinese: 紫禁城; pinyin: Zǐjìnchéng) is the imperial palace complex in the center of the Imperial City in Beijing, China. It was the residence of 24 Ming and Qing dynasty Emperors, and the center of political power in China for over 500 years from 1420 to 1924. The palace is now administered by the Palace Museum as a UNESCO World Heritage Site. The Forbidden City is arguably the most famous palace in all of Chinese history, and is the largest preserved royal palace complex still standing in the world.

The Forbidden City was constructed from 1406 to 1420, and was the imperial palace and winter residence of the Emperor of China from the Ming dynasty (since the Yongle Emperor) to the end of the Qing dynasty, between 1420 and 1924. The Forbidden City served as the home of Chinese emperors and their households and was the ceremonial and political center of the Chinese government for over 500 years. Since 1925, the Forbidden City has been under the charge of the Palace Museum, whose extensive collection of artwork and artifacts was built upon the imperial collections of the Ming and Qing dynasties. The Forbidden City was declared a World Heritage Site in 1987.

The complex claims to consist of 9,999 rooms in total, although experts have shown in recent years that the number only amounts to 8,886, covering 72 ha (720,000 m²)/178-acre. The palace exemplifies the opulence of the residences of the Chinese emperor and the traditional Chinese palatial architecture, and has influenced cultural and architectural developments in East Asia and elsewhere. UNESCO recognizes it as the largest collection of preserved ancient wooden structures in the world. Since 2012, the Forbidden City has seen an average of 14 million visitors annually, and received more than 19 million visitors in 2019. In 2018, the Forbidden City's market value was estimated at US$70 billion, making it both the world's most valuable palace and the most valuable piece of real estate anywhere in the world.

It was included in the first list of national priority protected sites in 1961. The palace is extremely important to the Chinese public and nation, who often view it as a cultural and heavenly link to their ancestors^{[citation needed]}.

The palace gained its name from its enormous scale and severely restricted access to all but the Emperor, the Imperial family, and Eunuchs; hence the Chinese term "Forbidden City" emerged. The punishment for unauthorised entry to the palace was immediate execution. The common English name "Forbidden City" is a translation of the Chinese name Zijincheng (紫禁城; lit. 'Purple Forbidden City'), which first formally appeared in 1576. Another English name of similar origin is "Forbidden Palace", though "city" is much closer to the original Chinese meaning.

The name "Zijincheng" has significance on many levels. Zi, or "purple", refers to the North Star, which in ancient China was called the Ziwei Star, and in traditional Chinese astrology was the heavenly abode of the Jade Emperor. The surrounding celestial region, the Ziwei Enclosure (紫微垣; Zǐwēiyuán), was the realm of the Jade Emperor and his family. The Forbidden City, as the residence of the terrestrial emperor, was its earthly counterpart. Jin refers to a prohibition or taboo. Cheng originally meant a castle, fortress, or fortification, but in modern Chinese, the character means city.

Today, the site is most commonly known in Chinese as Gugong (故宮), which means the "Former Palace". The museum which is based in these buildings is known as the "Palace Museum" (故宮博物院; Gùgōng Bówùyùan).

In the Ming and Qing dynasties, the Forbidden City was also known as Danei (大内) or "Palace City" (宮城; Gōngchéng).