Chandramukhi (transl. Moon-faced lady) is a 2005 Indian Tamil-language psychological horror comedy film written and directed by P. Vasu. It is a remake of Vasu's Kannada film Apthamitra (2004) which itself is based on the Malayalam film Manichitrathazhu (1993).The film stars Rajinikanth, Prabhu and Jyothika along with an ensemble supporting cast, including Vadivelu, Nayanthara, Nassar and Sheela. It revolves around a woman who suffers from dissociative identity disorder that affects a family, and a psychiatrist who intends to solve the case while risking his life.

Chandramukhi was produced by Prabhu and his brother Ramkumar Ganesan through their company Sivaji Productions, and is the company's 50th film. The soundtrack album and background score were composed by Vidyasagar. Cinematography was handled by Sekhar V. Joseph and editing was done by Suresh Urs. Principal photography began on 24 October 2004 and was completed in March 2005.

Chandramukhi was released on 14 April 2005 on the eve of the Tamil New Year. The film became a major box office success, the highest grossing Tamil film of the year with a theatrical run of 890 days at Shanti Theatre. The film won five Tamil Nadu State Film Awards, four Film Fans' Association Awards and two Filmfare Awards. Jyothika and Vadivelu were each awarded a Kalaimamani Award for their work on the film. A sequel Chandramukhi 2 was released in 2023.