Walter Bruce Willis (ব্রুস উইলিস) is a retired American actor. He achieved fame with a leading role on the comedy-drama series Moonlighting (1985–1989) and has appeared in over one hundred films, gaining recognition as an action hero for his portrayal of John McClane in the Die Hard franchise (1988–2013).

Willis's other credits include The Last Boy Scout (1991), Pulp Fiction (1994), 12 Monkeys (1995), The Fifth Element (1997), Armageddon (1998), The Sixth Sense (1999), Unbreakable, The Whole Nine Yards (both 2000), Tears of the Sun (2003), Sin City (2005), The Expendables, Red (both 2010), Looper (2012), and Glass (2019). In the last years of his career, he starred in many low-budget direct-to-video films, which were poorly received. Willis retired in 2022 due to aphasia, and was diagnosed with frontotemporal dementia in 2023.

Walter Bruce Willis was born on March 19, 1955, in Idar-Oberstein, West Germany; his mother, Marlene (1935–2013), was German, from Kassel, and his father, David Willis (1929–2009), was an American soldier. He has a younger sister, Florence, and two younger brothers, Robert (1959–2001) and David. After being discharged from the military in 1957, his father relocated the family to his hometown of Carneys Point, New Jersey. Willis has described his background as a "long line of blue-collar people". His mother worked in a bank and his father was a welder, master mechanic and factory worker.

Willis spoke with a stutter. He attended Penns Grove High School in Carneys Point Township, where his schoolmates nicknamed him "Buck-Buck". Willis joined the drama club, and found that acting on stage reduced his stutter. He was eventually elected student council president. He graduated from Penns Grove in 1973.

After graduating from high school, Willis worked as a security guard at the Salem Nuclear Power Plant and transported crew members at the DuPont Chambers Works factory in Deepwater. He turned to acting after working as a private investigator, a role he would later play in the comedy-drama series Moonlighting and the action-comedy film The Last Boy Scout.

Willis's acting role models are Gary Cooper, Robert De Niro, Steve McQueen, and John Wayne. He is left-handed. He resides in the Brentwood neighborhood of Los Angeles with his family.

On November 21, 1987, Willis married Demi Moore at the Golden Nugget Las Vegas. On December 20, the couple held a second reception for about 450 guests on a soundstage at Warner Bros. Studios Burbank. They have three daughters: Rumer (b. 1988), Scout (b. 1991), and Tallulah (b. 1994). Willis and Moore announced their separation on June 24, 1998. They filed for divorce on October 18, 2000, and the divorce was finalized later that day. Regarding the divorce, Willis stated, "I felt I had failed as a father and a husband by not being able to make it work." He credited actor Will Smith for helping him cope with the situation. He has maintained a close friendship with both Moore and her subsequent husband, actor Ashton Kutcher, and attended their wedding.

Throughout his film career, Willis has depicted several military characters in films such as In Country, The Siege, Hart's War, Tears of the Sun, Grindhouse, and G.I. Joe: Retaliation. Willis grew up in a military family. Willis has donated Girl Scout cookies to the United States armed forces. In 2002, Willis's then 8-year-old daughter, Tallulah, suggested that he purchase Girl Scout cookies to send to troops. Willis purchased 12,000 boxes of cookies, and they were distributed to sailors aboard USS John F. Kennedy and other troops stationed throughout the Middle East at the time.

Willis was a Lutheran, but says he no longer practices. In a July 1998 interview with George magazine, he said, "Organized religions in general, in my opinion, are dying forms. They were all very important when we didn't know why the sun moved, why weather changed, why hurricanes occurred, or volcanoes happened. Modern religion is the end trail of modern mythology. But there are people who interpret the Bible literally. Literally! I choose not to believe that's the way. And that's what makes America cool, you know?"

When asked by a Hollywood.tv reporter how he stays grounded in Hollywood, Willis said, "I just thank God every day for...everything great that's come my way."