The primary martial arts style used by John Wick in the film series is a unique blend known as Gun Fu, combining elements of Japanese Jiu-Jitsu, Brazilian Jiu-Jitsu, tactical 3-gun, and standing Judo. This diverse martial arts mix creates a fighting style characterized by fluid and dynamic movements, effective grappling techniques, and precision in both hand-to-hand combat and firearms handling. John Wick's combat style, reflective of these disciplines, is integral to his character, showcasing his lethal abilities in various combat situations.