Xidan (Chinese: 西单; Pinyin: Xīdān) is a major traditional commercial area in Beijing, China. It is located in the Xicheng District.

The Xidan commercial district incorporates the Xidan Culture Square, North Xidan Street, as well as many supermarkets and department stores. The Xidan Cultural Square is the largest venue for cultural events in downtown Beijing.

Xidan occupies around 80 hectares (197.7 Acres) within the Xicheng District.

The name Xidan (literally, "West Single") came from the paifang that existed on one of the streets there. In this context, the name "Xidan" refers to the single (单) paifang that existed on the west side (西) of the city.

The paifang was recently rebuilt, and now stands at the Xidan Culture Square.

Xidan began to develop in the Ming Dynasty as an area alongside the passage for traders from Southwestern China to enter Beijing. Restaurants and shops were eventually built for these merchants. Eventually, as the Western part of the city became the residential area for officials, Xidan became a commercial area. The location of several government agencies when Beijing was under the administration of the Republic of China also helped Xidan's economic growth.