This is a list of organisms that are known to kill humans. Inclusion on this list requires a certain notoriety, such as that gained from news reports. Each included organism must have repeatedly killed humans in a defined way. For the sake of inclusiveness, "organisms" includes viruses, in addition to animals, plants and others.

The list is organized by method, such as biting. For the sake of avoiding anthropomorphizing organisms, this list avoids distinctions based on supposed "aggressiveness" or "defensiveness".