Jhonen C. Vasquez is an American cartoonist, writer, producer, and director. He is best known for creating the Johnny the Homicidal Maniac comic book series and the Nickelodeon animated series Invader Zim.

Johnny the Homicidal Maniac is the first comic book by Jhonen Vasquez. The series tells the story of a young man named Johnny “Nny” C. as he explores the psychological and possibly supernatural forces which compel him to commit a string of murders with which he always seems to get away. JtHM began as a comic strip in the 1990s, then ran under alternative comics publisher Slave Labor Graphics as a limited series of seven issues, later collected in the trade paperback Johnny the Homicidal Maniac: Director's Cut. The series produced three spin-offs: Squee!, I Feel Sick and Fillerbunny.