Stanislas "Stan" Wawrinka (French: [vavʁiŋka]; born 28 March 1985) is a Swiss professional tennis player.

He has won two Grand Slam singles titles in his career: the 2014 Australian Open and the 2015 French Open, and has reached a world ranking of no. 3, obtained on 27 February 2014 and held for several months. He also won an Association of Tennis Professionals (ATP) Masters 1000 tournament at the Monte-Carlo Masters in 2014, and was a finalist at the Rome Masters in 2008 and the Madrid Masters in 2013. Furthermore, he won a gold medal for Switzerland in the men's doubles event at the 2008 Summer Olympics, partnering with Roger Federer, and was part of the Swiss team that won the Davis Cup in 2014. He played in the longest doubles match in history at the Davis Cup tie against the Czech Republic in 2013, partnering with Marco Chiudinelli.