Valentino Rossi (; Italian: [valenˈtiːno ˈrossi]; born 16 February 1979) is an Italian former professional motorcycle road racer and nine-time Grand Prix motorcycle racing World Champion. Nicknamed The Doctor, he is widely considered to be one of the greatest motorcycle racers of all time, with some labelling him as the greatest ever. He has nine Grand Prix World Championships to his name, seven of which were in the premier 500cc/MotoGP class. He holds the record of most premier class victories, with 89 victories to his name. He won premier class World Championships with both Honda and Yamaha. He is also the only road racer to have competed in 400 or more Grands Prix, and rode with the number 46 for his entire career.

After graduating to the premier class in 2000, Rossi won the final 500cc World Championship (becoming the last satellite rider to win the top-class title to date) and the 8 Hours of Suzuka with Honda in 2001. He also won MotoGP World Championships with the factory Honda Team in 2002 and 2003 and continued his run of back-to-back championships by winning the 2004 and 2005 titles after leaving Honda to join Yamaha. He lost the 2006 title with a crash in the final round at Valencia. In 2007 he ultimately finished third overall, before regaining the title in 2008 and retaining it in 2009. After a 2010 season marred by a broken leg and no title defence, he left Yamaha to join Ducati, replacing Casey Stoner for the 2011 and 2012 seasons, and endured two losing seasons with the Italian marque.

Rossi returned to Yamaha in 2013 and finished fourth in the standings followed by three successive runner-up positions in 2014, 2015 and 2016. His best chance of winning a tenth title came in 2015, where he led the standings for most of the season, finishing five points behind teammate Jorge Lorenzo, the eventual champion. 2017 was the final season he achieved over 200 points in the championship and he took his final race victory at the 2017 Dutch TT at the age of 38. After three winless seasons with the factory Yamaha team, he moved to Petronas SRT for 2021, retiring after only one season with the satellite Yamaha team and failing to achieve a podium for the first time in a career spanning 26 seasons in Grands Prix. The dominant force in MotoGP in the 2000s, all of Rossi's seven premier class titles came in this decade, including 77 race wins and 48 pole positions. In the ensuing 12 seasons, he managed 12 race wins and seven pole positions. During this period, Rossi was the 6th most successful rider in terms of total race victories.

Rossi was inducted into the MotoGP Hall of Fame as an official Legend by the FIM at the awards ceremony after the conclusion of the 2021 season. His #46 bike number was retired at the 2022 Italian Grand Prix. Rossi owns the Racing Team VR46, which competes in both Moto2 and MotoGP as of 2022. He also plans to be involved in and administering his motorcycle racing team VR46. In addition to his team management role, Rossi competes full-time in GT World Challenge Europe, driving an Audi R8 LMS for Team WRT.