Hypersexuality, also known as compulsive sexual behavior disorder or sex addiction, is an intense focus on sexual fantasies, urges, or behaviors that cannot be controlled. It is a term used for a presumed mental disorder causing people to engage in or think about sex to a point of distress or impairment. Hypersexuality may be a primary condition or a symptom of another medical disease or condition, such as Klüver–Bucy syndrome or bipolar disorder, or may present as a side effect of medication such as drugs used to treat Parkinsons disease.

Some signs that a person may have compulsive sexual behavior include repeated and intense sexual fantasies, urges, and behaviors that take up a lot of time and feel beyond their control, feeling driven or having frequent urges to do certain sexual behaviors, feeling a release of tension afterward but also feeling guilt or deep regret, trying without success to reduce or control sexual fantasies, urges, or behavior, using compulsive sexual behavior as an escape from other problems such as loneliness, depression, anxiety, or stress, and continuing to engage in sexual behaviors in spite of them causing serious problems.

Hypersexual behaviors are viewed variously by clinicians and therapists as a type of obsessive-compulsive disorder (OCD) or "OCD-spectrum disorder," an addiction, or a disorder of impulsivity. However, a number of authors do not acknowledge such a pathology and instead assert that the condition merely reflects a cultural dislike of exceptional sexual behavior.