Drowning by Numbers is a 1988 motion picture directed by Peter Greenaway. Its plot centers on three women, all called Cissie Colpitts, each of whom murders her husband by drowning. Through the course of the film the numbers one to one hundred appear in order, sometimes seen in the background, sometimes spoken by the characters.

The three Cissie Colpittses are played by Joan Plowright, Juliet Stevenson, and Joely Richardson. Bernard Hill plays the coroner Madgett, who is cajoled into covering up the three crimes. The structure, with similar stories repeated three times, is reminiscent of a fairy tale. The link to folklore is further established by Madgett's son Smut, who recites the rules of various unusual games played by the characters as if they were ancient traditions.

The musical score is by Michael Nyman, and is entirely based on themes taken from the slow movement of Mozart's Sinfonia Concertante in E flat, K364. Nyman had previously used this piece as the basis for part of the score for Greenaway's The Falls. It is heard in its original form immediately after each drowning.