Giovanni Fonio (born 7 May 1998) is an Italian tennis player. Fonio has a career high ATP singles ranking of 435 achieved on 25 October 2021. He also has a career high doubles ranking of 475 achieved on 10 February 2020. Fonio has won 1 ATP Challenger doubles title at the 2021 Antalya Challenger III with Riccardo Bonadio.