Daniela Hantuchová (Slovak pronunciation: [ˈdaɲiela ˈɦantuxoʋaː]; born 23 April 1983) is a Slovak tennis player. She turned professional in 1999 and had her breakthrough year in 2002, when she won her first WTA tournament, the Indian Wells Masters, defeating Martina Hingis in the final and becoming the lowest-ranked player to ever win the tournament. She also reached the quarterfinals of that year's Wimbledon Championship and US Open, ending the year in the top 10. She was part of the Slovak team that won the 2002 Fed Cup and the 2005 Hopman Cup.
Hantuchová reached her highest ranking, fifth, in January 2003, after reaching the quarterfinals of the Australian Open. She has gone on to win a further seven WTA tournaments, including the Indian Wells Masters for a second time in 2007 and most recently the 2015 Thailand Open. She also reached the semifinals of the Australian Open in 2008, the furthest she has progressed in a Grand Slam. She is the most successful Slovak tennis player of all time and became only the 37th woman in the Open Era to reach 500 career wins when she beat Laura Robson in the second round of the Aegon Classic in June 2013.
Hantuchová is also an accomplished doubles player. In 2005, she completed the career Grand Slam in mixed doubles, becoming only the fifth female tennis player to do so. She won the mixed doubles at Wimbledon in 2001 with Leoš Friedl, at the Australian Open in 2002 with Kevin Ullyett, at the French Open in 2005 with Fabrice Santoro and at the US Open in 2005 with Mahesh Bhupathi. She has also reached the finals of the mixed doubles at Wimbledon in 2002 with Ullyett and the finals of the women's doubles at the Australian Open in 2002 with Arantxa Sánchez Vicario, at the French Open in 2006 with Ai Sugiyama and at the Australian Open in 2009 with Sugiyama.
Since December 2014 Hantuchová has been coached by Carlos Rodríguez. Her WTA Tour mentor in the "Partners for Success" program was Martina Navratilova, who was her doubles partner for a brief period in early 2005.