To protect the wizarding world from the dragons
- Unidentified wizard #1: "I pull down about a hundred sacks of Galleons a year! I'm a dragon killer for the Committee for the Disposal of Dangerous Creatures."
- Unidentified wizard #2: "No, you're not! You're a dishwasher at the Leaky Cauldron… but I'm a Vampire Hunter, I've killed about ninety so far -"
- — A group of wizards fighting over the affections of a group of Veelas[src]
A dragon killer is someone who kills dragons as an occupation. Although not confirmed, dragon killers are presumably employed by the Committee for the Disposal of Dangerous Creatures.
In the late 19th century, Peruvian Vipertooth numbers once went on an alarming increase and became a serious threat to wizards and Muggles alike. The International Confederation of Wizards was forced to send an extermination squad in to reduce the Vipertooth population.
During the Quidditch World Cup in 1994 an unidentified wizard was trying to impress a group of Veelas and claimed to be a dragon killer who earned "a hundred sacks of Galleons a year". Another unidentified wizard spoke up claiming that the supposed dragon killer was in fact a dishwasher at the Leaky Cauldron and that he was a Vampire Hunter himself.
- Harry Potter and the Goblet of Fire (Mentioned only)