Perpetual Motion is an independent Chinese film directed by Ning Ying. The film follows four wealthy, high-powered women living in Beijing during the Chinese New Year. The film had its North American premiere on September 10, 2005 at the 2005 Toronto International Film Festival. Perpetual Motion was co-written by Ning, musician and author Liu Sola, and publisher Hung Huang (Hung and Liu also star) and was produced by Beijing Happy Village, Ltd.

The film opened in Chinese cities in late February 2006 to some controversy due to its depiction of assertive, sexually confident women. The version shown was slightly edited compared to the version shown abroad in Toronto and Venice, with some of the more explicit discussions on sex as well as a scene involving the four main characters listening to an old revolutionary song in high heels and makeup being edited or cut. Given its content, Perpetual Motion is often referred to as a Chinese version of the American television series Sex and the City.