Simona Halep (Romanian pronunciation: [simo'na haˈlep]; born 27 September 1991) is a Romanian professional tennis player. She is the current world No. 1 on the WTA Tour, a ranking she first achieved in October 2017. Halep first broke into the world's top 50 at the end of 2012, reached the top 20 in August 2013, and finally the top 10 in January 2014. She won her first 6 WTA titles in the same calendar year in 2013 (a feat that was last achieved by Steffi Graf in 1986 when she won her first 7), being named the WTA's Most Improved Player at its end, as well as being named ESPN Center Court's 2013 Most Improved Player.

Born in Constanța two years after the Romanian Revolution, Halep began playing tennis at four years old, and was practicing daily by the age of six; she moved to Bucharest at 16 years old to further her career in the sport. Halep won her first major tournament at the 2018 French Open, having previously lost in the 2014 French Open and 2017 French Open finals. She also reached the final of the 2014 WTA Finals, losing to Serena Williams in straight sets after having defeated her earlier in the tournament. Halep continued her success throughout the 2015 and 2016 seasons winning 3 titles in each respective season (including 2 Premier Mandatory titles) and remaining within the Top 10.

Halep was the most clicked player on WTATennis.com for two consecutive years (2014–2015), when she was awarded the WTA Most Popular Player of the Year prize. After the 2017 Wimbledon Championships, Simona Halep became the active player with the most consecutive weeks within the Top 10. Halep has also won WTA's Fan Favorite Singles Player in 2017.

She was given the award of Cetățean de onoare ("Honorary Citizen") of the city of Bucharest in 2018.