Black magic is the belief of practices of magic that draws on assumed malevolent powers. This type of magic is invoked when wishing to kill, steal, injure, cause misfortune or destruction, or for personal gain without regard to harmful consequences to others. As a term, "black magic" is normally used by those that do not approve of its uses, commonly in a ritualistic setting; the argument of "magic having no colour, and it is merely the application and use by its user," backs the claim that not everything termed as "black magic" has malevolent intentions behind it, and some would consider it to have beneficial and benevolent uses. These uses could include killing diseases or pests.

Practitioners who use magic in this way argue that the effect itself is malevolent by causing death to insects (as in the above example), but as an indirect consequence of black magic, good can be a result, such as in the form of less pests around. In this school of thought, there is no separation between benevolent and malevolent magic as there is no universal morality against which magic can be measured. A rather different view on Black Magic is used in the system of Chaos Magick. In this branch of occult practice, spells sometimes correspond to colours, depending on the supposed effect (i.e, red-magick, which is magic concerned with combat, such as low-level curses). Black Magic, according to Chaos Magick, corresponds to magic that is performed around the themes of death, separation, severance and entropy. This can refer to powerful curses meant to bring the strongest effect, spells to sever emotional ties to objects or people, and so on.

In fiction, black magic will quite frequently be synonymous with evil, such is the case in Rosemary's Baby, J.K. Rowling's Harry Potter series (referred to as the dark arts in the novels), and Shakespeare's Macbeth, with many other examples existing. In many popular video games, such as Final Fantasy, white and black magic is simply used to distinguish between healing/defensive spells (such as a "cure") and offensive/elemental spells (such as "fire") respectively, and does not carry an inherent good or evil connotation.