Ouellet was born in Montreal, Quebec, but grew up in Edmundston, New Brunswick. In high school, Ouellet was the only girl in her class, and ran the school's fashion show. She also began developing a range of makeup products. Ouellet began her modelling career as a beauty pageant contestant, winning Miss Hawaiian Tropic Canada 2003 and finishing second at the International Finals of Miss Hawaiian Tropic 2004. She was also on the cover of Playboy's 2007 Girls of Canada calendar.

On the September 22, 2006 episode of SmackDown!, Ouellet, known as simply Maryse, was shown on the TitanTron welcoming the Montreal viewers in French to the season premiere of SmackDown! on the CW Network. Maryse made her first official televised appearance on the May 21, 2007 episode of Raw to present American Rapper Timbaland's new music video for the single "Throw It on Me", in which she had appeared.

In April 2007, she appeared alongside fellow WWE Divas Ashley, Torrie Wilson, Brooke Adams, Layla, and Kelly Kelly in Timbaland's music video "Throw It On Me" featuring The Hives.

By the time she began appearing regularly on SmackDown at the beginning of 2008, she had adopted a snobby attitude and become a villainous character. On the March 7, 2008 episode of SmackDown, Maryse competed in a swimsuit contest against Victoria, Michelle McCool, Cherry, and Eve Torres, which ended in a brawl between Maryse and Torres. The following week, she was the first eliminated from another swimsuit competition. On March 28, Maryse competed in a "Wet and Wild" match, teaming with Victoria against Cherry and McCool in a losing effort. On a "SmackDown after the bell" video on WWE's website, the tag team Deuce 'n Domino dumped Cherry, who had been their manager, and replaced her with Maryse. Maryse then insulted Cherry, only for Cherry to slap her. On the May 16 episode of SmackDown, Maryse made her in-ring debut in a loss to Cherry, though she defeated Cherry in a rematch the following week. On the June 6 episode of SmackDown!, SmackDown General Manager Vickie Guerrero announced the creation of the WWE Divas Championship, and that same night the Divas competed in a Golden Dreams match to qualify for the championship match at The Great American Bash, which was won by Natalya. On the July 4, 2008 episode of SmackDown!, she competed again in another Golden Dreams match to face Natalya for the championship, however she failed to win. For several weeks, Maryse competed in six-person tag team matches with Victoria and Natalya against Cherry, Michelle McCool and Maria. She suffered a minor broken nose after receiving a bulldog from Maria in August 2008.

Ouellet also appeared in the January 2009 issue of Muscle & Fitness, along with Eve Torres and Michelle McCool. She and John Morrison were interviewed on Eurosport in the same year. She also made a special appearance on Redemption Song, which was hosted by WWE Wrestler Chris Jericho, along with Candice Michelle, Mickie James, and Eve Torres. She has also appeared in several newspaper interviews, including Tokyo Headline, and was on the cover of Sessions Magazine in October 2010.

Maryse has appeared in four WWE video games. She made her in-game debut at WWE Smackdown vs. Raw 2010, later appearing in WWE Smackdown vs. Raw 2011, WWE '12, and returned in WWE 2K18.

Ouellet is a native speaker of French, fluent in English, and she is able to read Spanish, although she cannot speak it. Ouellet has a tattoo of her late father's name, Guy, on her left wrist. She has a degree in Business administration, and holds a black belt in martial arts. Her favorite Actress is Scarlett Johansson, her favorite bands are Simple Plan and Nickelback, and she loves techno music. Ouellet is a vegan and an avid supporter of animal rights and gay rights, and posed for the NOH8 campaign in 2011. Ouellet is Catholic.

In 2012, Maryse was featured on the cover of Le Journal de Montréal, and on MDA Show of Strength with The Miz and other celebrities. In 2015, Ouellet had roles in Sharknado 3: Oh Hell No! and in Santa's Little Helper, the latter starring Ouellet's husband, The Miz. In the same year, she appeared on the E! reality television series WAGS. In 2016, it was announced that Maryse would appear as a main cast member on the sixth season of Total Divas, which prompted her return to WWE. In June 2017, Maryse along with Miz were cover of the DUB Magazine with a Jeep car. In 2018, Maryse along with The Miz will star in a reality television series titled Miz & Mrs.

Beginning in late 2013, Ouellet began working as a realtor in Los Angeles after spending a year earning her real estate license.

In 2013, Ouellet got engaged to longtime boyfriend and fellow Wrestler Mike Mizanin, best known by his ring name The Miz. The two were married in The Bahamas on February 20, 2014. The couple reside in Austin, Texas. The couple announced on September 11th episode of RAW that they are expecting their first child.

Following a hiatus due to the shoot of a WWE film, Maryse returned to WWE television on the June 27 episode of Raw, where she helped Miz to retain his championship against Kane after she faked an ankle injury. After being drafted to Smackdown as part of the 2016 WWE draft which took place on July 19, Ouellet made her first appearance for the brand on July 26, where she co-hosted a Miz TV segment along her husband before being interrupted by Randy Orton, who challenged Miz to a non-title match, in which he was subsequently defeated. At Backlash, Maryse successfully helped Miz to retain the Intercontinental Championship by spraying something at Dolph Ziggler whilst Miz distracted the Referee. The following week, SmackDown General Manager Daniel Bryan announced a rematch for the championship due Maryse's interference at Backlash. On September 20, Miz retained the championship over Ziggler. On October 9, at No Mercy Miz lost the Intercontinental Championship to Ziggler in a title vs career match when Maryse was banned from the ringside along with The Spirit Squad (Kenny and Mikey), who was contracted by her to help Miz, ending Miz's reign at 188 days. On November 8 episode of SmackDown, Maryse went on to speak in Miz's name due Miz refuse to speak with Daniel Bryan. At that night, Maryse accepted Bryan's offer to Miz face Ziggler the following week for the Intercontinental Championship in the 900th episode of SmackDown. Later that night, Bryan would state on Talking Smack that if Ziggler successfully retains his championship, The Miz and Maryse would be traded to Raw for someone else. On November 15 at the 900th episode of SmackDown, Maryse helped Miz to win the championship for the sixth time and also retain it at Survivor Series against Sami Zayn.

On December 20, episode of SmackDown, Maryse was banned from the ringside after an attempt to apply a eye poke on Apollo Crews during a championship match for Miz's Intercontinental Championship; After the match, Miz was interviewed by Renee Young who slapped him after a joke involving her and Dean Ambrose. On December 27, episode of SmackDown, Maryse confronted Renee Young in a backstage segment before Ambrose attacked Miz. On January 3, 2017, episode of SmackDown, Maryse slapped both Ambrose and Young in different occasions, before interfering in the championship match between Miz and Ambrose, slapping Ambrose again and being banned from ringside before Ambrose defeated Miz for the championship. Later on Talking Smack, Maryse was fined $5,000 for slapping Young.

On March 27, 2018, Maryse gave birth to their first child, a daughter named Monroe Sky.