Samuel Groth (born 19 October 1987) is an Australian former professional tennis player. His highest ATP singles ranking is World No. 53, which he reached in August 2015. His career high in doubles was World No. 24, reached in February 2015. Groth's best singles result was a semi-final appearance at the 2014 Hall of Fame Tennis Championships. He hit the fastest serve on record at 263 km/h (163.4 mph) in 2012 at the ATP Challenger in Busan.