He is the grandson of Gory Guerrero; the son of Chavo Guerrero, Sr.; the nephew of Eddie Guerrero, Hector Guerrero, Mando Guerrero, and Enrique Llanes; and the cousin of Javier Llanes and Hector Mejia. He is currently signed to World Wrestling Entertainment wrestling on its ECW brand. His grandfather, Gory Guerrero, was one of the most famous wrestlers in Mexican history. His father, Chavo Guerrero, Sr., was also a legendary wrestler in Mexico and worked in WWE as a part-time wrestler and full-time manager. One of his uncles, Eddie Guerrero, was one of WWE's biggest stars. Eddie performed for the SmackDown! brand, as did Chavo Sr. (aka Chavo Classic). Chavo Jr. has two other uncles (Mando and Hector) who have had successful careers in the business.
Chavo Guerrero enjoyed most of his success in WCW during 2000 and 2001 during which he was the WCW Cruiserweight Champion. Guerrero engaged in a memorable feud against "Sugar" Shane Helms, to whom he lost the Cruiserweight Title on the last episode of WCW Monday Nitro.
Chavo Guerrero spent time as an undercard wrestler in the company, which was soon rebranded World Wrestling Entertainment, before becoming a trainer for WWE's second Tough Enough competition. Soon after returning to the active roster, Chavo was aligned with his uncle Eddie, forming the tag team Los Guerreros. In contrast to his previous WCW storyline with his uncle, Chavo fully adopted his uncle's policy of "Lie, Cheat and Steal" to win matches as part of the gimmick. The duo would go on to win the WWE Tag Team Championship twice, feuding with such teams as Edge and Rey Mysterio and Team Angle.
In one angle, his uncle's singles title ambitions made Chavo jealous and Chavo turned on Eddie, broke from the team, and became a heel again. He was soon joined by his father Chavo Sr. who sided with his son instead of his brother. Eddie Guerrero defeated Chavo at the 2004 Royal Rumble. After the feud with Eddie finished, Chavo became a wrestler in the cruiserweight division and captured the WWE Cruiserweight Championship on several occasions.
Chavo returned several months later as a face again, exacting revenge from a now-heel, Kidman, but shortly returned to his third heel persona after receiving a heel reaction after facing then-cruiserweight champion Funaki in a losing effort during a SmackDown! show in Japan.
On June 30, 2005, Chavo became one of the last minute trades in the 2005 WWE Draft, which saw him jump from SmackDown! to Raw. The next week, on Raw, he denounced his Hispanic heritage in favor of the Anglo-American way. This came after two weeks of being battered by the Mexican faction, The Mexicools. It led to the changing of his persona to Kerwin White, a stereotypical, middle-class, white, Anglo-American man. He dyed his hair blond and often drove a golf cart to the ring which held his golf clubs. His new catch phrase became the pun, "If it's not White, it's not right." The phrase would later change to "If it's not Kerwin White, it's not right" because the original sounded racist. It would later be phased out entirely.
Soon after his debut, White started making suggestive remarks towards African Americans, specifically directed towards Shelton Benjamin. On an episode of Raw, Kerwin cost Shelton a match against Rob Conway. Benjamin defeated Kerwin White by disqualification the following week when Kerwin attacked Shelton with his golf club. At Unforgiven, White was beaten by Benjamin. White then hired Nick Nemeth to help him in his matches.
Later that afternoon, Chavo appeared at a press conference with WWE Chairman Vince McMahon to address Eddie's death. They announced that both shows that week would be tributes to Eddie. These events resulted in Chavo dropping the Kerwin White gimmick and wrestling under his real name as a face to continue the Guerrero legacy. As Chavo Guerrero, he defeated John "Bradshaw" Layfield (JBL) on the November 18, 2005 episode of SmackDown!, using the "Three Amigos" triple suplexes and the Frog Splash in tribute to Eddie. He also used the cheating tactic of throwing a steel chair to an opponent who catches it (while laying down himself) as the referee turns around and disqualifies the opponent, which Eddie made famous.
A month later, on the February 24, 2006 edition of Smackdown!, Chavo attacked Randy Orton with the Three Amigos and the frog splash when Orton began to insult Eddie Guerrero, and talk about the heritage of the Guerreros. Chavo was soon dragged out by security, but kept yelling to Orton "You forgot about the Guerreros - the greatest wrestling family!" and "You forgot me!".
On the February 27, 2006 edition of Raw, Chavo faced off against Shelton Benjamin in a qualifying match for the Money in the Bank Ladder Match at WrestleMania 22. During the match, Randy Orton interfered and hit Guerrero with the RKO. This allowed Shelton to get the pinfall victory.
On the April 3, 2006 edition of Raw, Chavo came out to address the crowd. He thanked the fans for all the support they had given him and his family and for keeping his Uncle Eddie's spirit alive, but he expressed his disappointment in not having a title match at WrestleMania 22. He felt that night would become his WrestleMania and he was going to dedicate his match to his Uncle Eddie. He proceeded to challenge Shelton Benjamin for the WWE Intercontinental Championship, but ended up losing after he missed a Frog Splash, allowing Benjamin to connect with his T-Bone Suplex finisher. In a segment that aired on WWE Unlimited, an emotional Chavo Guerrero decided to quit WWE after believing he had let his family, Eddie, and the fans down and expressed his doubts about being a wrestler.
On May 13, 2006 Chavo appeared at a SmackDown! house show in El Paso, TX, defeating Finlay. Chavo also appeared at Judgment Day to support Rey Mysterio. Chavo would then support Mysterio for a few weeks on SmackDown!. At the Great American Bash, Chavo interfered in Rey Mysterio's World Heavyweight Championship match, ostensibly to help Mysterio. However, Chavo turned heel once more by bashing Rey with a steel chair, which allowed challenger King Booker to win the match.
On the August 4, 2006 episode of SmackDown!, Chavo accused Rey of using Eddie's name to succeed, claiming that Rey disrespected Eddie's memory. Chavo went on to beat Rey Mysterio thanks to a frog splash at SummerSlam, after Vickie Guerrero accidentally knocked Mysterio off the top turnbuckle. On August 25, Vickie Guerrero came down to the ring to apologize to Rey Mysterio and Chavo. Vickie ended up turning on Mysterio by hitting him in the back with a steel chair. The following week on SmackDown!, Vickie Guerrero announced herself as being Chavo's new manager. Weeks later on October 8, 2006, Rey Mysterio gained his revenge on Guerrero by defeating him in a Falls Count Anywhere match at No Mercy. Guerrero eventually challenged Mysterio to an "I Quit" match, in which Guerrero won after inflicting multiple chair shots to Rey Mysterio. As per the condition of the match, Mysterio was forced to leave SmackDown!, possibly ending the emotional feud between the two.
A week later, Chris Benoit, another old friend of Eddie's, tried talking to Vickie Guerrero, but she would not hear it. It started a feud between Chavo and Benoit and both men would have numerous confrontations over the following weeks. Benoit defeated Chavo to retain the WWE United States Championship at the Survivor Series. After weeks of continued interaction, the two faced off in a U.S. title rematch at Armageddon that Chavo also lost when he tapped out to a Sharpshooter. Chavo got yet another rematch the following Friday, losing the match after Vickie hit Benoit with the title belt. Chavo snapped after the match, knocking over Vickie and attacking Benoit. The feud concluded with Benoit forcing Guerrero to submit in a No-Disqualification match.
The next day, Chris Benoit (a close friend of Chavo), his wife Nancy, and their son Daniel were found dead at their home (their deaths have been since ruled a double homicide-suicide). Chavo was reportably one of the last people to talk to Benoit and one of the people Benoit sent text messages to before killing himself. He would then retain his title on the June 29 edition of SmackDown! in a triple threat match that also involved Jamie Noble and Funaki, when he pinned Funaki after the Gory Bomb. Following the match he climbed the turnbuckle and pointed to the ceiling of the AT&T Center making a gesture with two fingers, perhaps in reference to the death of Eddie Guerrero and the recent death of Benoit.
At The Great American Bash, he lost the Cruiserweight title in a Cruiserweight open when Hornswoggle pinned Noble (Hornswoggle wasn't originally in the match but was in the ring when the bell rang, thus becoming an official entrant).
Guerrero would then turn his attention to Rey Mysterio, whom he had (kayfabe) put out of action in 2006. Before Mysterio's return at SummerSlam, Guerrero mocked Mysterio's knee injury and taunted him during matches. He was, however, unable to defeat Mysterio at the pay-per-view. He then lost an "I Quit" re-match to Mysterio, when Mysterio continued to assault Chavo's left knee with a steel chair, thus (kayfabe) injuring him. This allowed Guerrero to have time off to serve his suspension for violating the WWE Wellness Policy. Chavo Guerrero returned to the roster on the November 9, 2007 episode of SmackDown! in a dark match against OVW wrestler Charles "The Hammer" Evans.
Chavo remained inactive until the December 18 edition of ECW, where he appeared after the main event between United States Champion Montel Vontavious Porter and ECW Champion CM Punk and proceeded to attack the vulnerable ECW champion, sending a message that he wanted a title shot.
With the beginning of 2008, Chavo Guerrero entered a feud with CM Punk regarding his ECW title. Chavo would challenge Punk to several matches until he finally won the third via countout after interference from World Heavyweight Champion Edge to earn a championship match. The previous matches he lost via countout and disqualification. On the January 22 edition of ECW, Chavo defeated CM Punk in a No Disqualification match to win the ECW Championship following interference from Edge. (In the process he proclaimed Edge and company as his "familia".) . He then successfully defended his title against CM Punk at No Way Out and on the March 4 edition of ECW, both times pinning Punk after a frog splash. At Wrestlemania XXIV, Chavo lost the ECW Championship to Kane in a record eight seconds. Shortly afterwards, Bam Neely debuted to act as his bodyguard. Shortly after losing the ECW Championship, Chavo had several attempts to regain the ECW Championship including losing to Kane at Backlash and also failing to become the #1 contender at One Night Stand. after aiding Edge in several attempts to banish The Undertaker from the WWE, Edge turned on all La Familia teammates, including Chavo. Afetr this, Chavo returned to singles and tag team action with Bam Neely, feuding with ECW newcomers Evan Bourne and Ricky Ortiz. After a lengthy rivalry with Bourne, Chavo attempted to regain the ECW Championship as a participant in the ECW Championship Scramble at Unforgiven, however coming up short.
On August 30, 2007, Guerrero, along with nine other WWE Wrestlers were named by Sports Illustrated to be given illegal steroids not in compliance with the Talent Wellness program. Guerrero received somatropin, nandrolone, and anastrozole between April 2005 and May 2006. Chris Benoit, Eddie Guerrero, and Brian Adams were also discovered to have been given steroids prior to their death during this investigation, as well as former WWE Wrestler Sylvain Grenier.