Jeffrey "Jeff" Nero Hardy (born August 31, 1977) is an American (United States) professional wrestler (Professional wrestling), currently signed to Total Nonstop Action Wrestling (TNA). He is best known for his time in the World Wrestling Federation/Entertainment (World Wrestling Entertainment) (WWE).

Before gaining prominence in WWE, Hardy performed for the Organization of Modern Extreme Grappling Arts (OMEGA), a promotion he ran with his brother Matt (Matt Hardy). After being signed by WWE, the brothers worked as jobbers (Job (professional wrestling)#Jobbers), before gaining notoriety in the tag team division, partly due to their participation in Tables, Ladders, and Chairs matches. With the addition of Lita (Amy Dumas), the team became known as Team Xtreme (Hardy Boyz#Team Xtreme) and continued to rise in popularity. As a tag team wrestler, Hardy is a six-time (List of World Tag Team Champions (WWE)) World Tag Team Champion (World Tag Team Championship (WWE)) and a one-time (List of WCW World Tag Team Champions) WCW Tag Team Champion (WCW World Tag Team Championship).

Hardy has also experienced success as a singles wrestler and is a three-time World Champion, having held the WWE Championship once and World Heavyweight Championship (World Heavyweight Championship (WWE)) twice, a four-time (List of WWE Intercontinental Champions) Intercontinental Champion (WWE Intercontinental Championship), and has held the Light Heavyweight (WWF Light Heavyweight Championship), and European Championship (WWE European Championship)s once each. He is also a former Hardcore Champion (WWE Hardcore Championship), having held the championship on three occasions (List of WWE Hardcore Champions). He received his first major main event (Card (sports)#Main event) push (Glossary of professional wrestling terms#Push) towards the end of 2007, including challenging for the WWE Championship at the Royal Rumble (Royal Rumble (2008)) in 2008, and eventually won the WWE Championship at the Armageddon (Armageddon (2008)) pay-per-view in December 2008.

Moreover, Hardy is involved in motocross, music, painting, and other artistic endeavors. He is currently a member of the band NowrapPeroxwhy?gen.