Kuchisake-onna (口裂け女, Kuchisake-onna) ("Slit-Mouth Woman") refers to both a story in Japanese mythology, as well as a modern version of the tale of a woman, mutilated by a jealous husband, and returned as a malicious spirit bent on committing the same acts done to her.

The legend is said to originate with a young woman who lived hundreds of years ago (some versions of the legend state the Heian period) and was either the wife or concubine of a samurai. She is said to have been very beautiful but also very vain, and possibly cheating on her husband. The samurai, extremely jealous and feeling cuckolded, attacked her and slit her mouth from ear to ear, screaming "Who will think you're beautiful now?"

The urban legend picks up from this point, stating that a woman roams around at night (especially during foggy evenings), with her face covered by a surgical mask, which would not be especially unusual, as people with colds often wear masks for the sake of others. When she encounters someone (primarily children or college students), she will coyly ask, "Do you think I'm beautiful?" ("Kirei da to omou?") or a similar question, at the same time taking off her mask, revealing her mutilated mouth. The victim will usually run away screaming, and the Kuchisake-onna will chase after, carrying a bladed weapon, such as a knife. She will catch the victim on the doorstep of their home and kill them there.

The legend says that the only way to avoid being chased is to give a middle-ground answer to Kuchisake-onna's question. Answering "yes" or "no" will result in a chase, and only answering something along the lines of "You look ordinary" will make her leave the victim alone. If a victim is chased, the only way to distract the Kuchisake-onna is by throwing her a favourite brand of candy.

During the spring and summer of 1979, rumors abounded throughout Japan about sightings of the Kuchisake-onna having hunted down children.

In 2004, a similar legend spread throughout cities in South Korea, though this may have been fueled by tales of the 1979 cases in Japan, as well as a 1996 Japanese film.

The 1996 film Kuchisake-onna gives the legend a modern origin as the result of a plastic surgery gone horribly awry. Many anime series refer to the legend as well, often in throwaway lines. This is especially true during the 1980s when the 1979 reports were fresh in people's memories.

Several kuchisake-onna appear in the manga and anime series Hell Teacher Nūbē; in this series they are shown in a much more sympathetic light.

An episode of the anime Ghost Stories featuring the character was initially scheduled to air on November 5, 2000, but the episode was discontinued when many people complained to Fuji TV because they thought the facial feature looked like cleft palate. [1]

In the movie Ring, a brief discussion near the beginning of the film centers around how real life events lead to urban legends being born. At one point a character mentions that a recent car crash in which a woman was mutilated gave rise to a surge of alleged Kuchisake-onna sightings. This is a possible reference to the spate of reports in 1979.

Hideo Yamamoto's manga Ichi the Killer features a yakuza enforcer named Kakihara with a similar disfigurement.

The American adaptions and the Japanese film series The Grudge deals with a malicious spirit that has a similar motive of making others feel their pain after a violent death. Admittedly, the character of Kayako Saeki is a more sympathetic character, but the premises are too similar to ignore.

There is also another Japanese film adaptation, "Kuchisake Onna" directed by Koji Shirasihi, released 17 March 2007 in Japan that deals with the slit-mouthed spirit seeking victims with a pair of scissors.