Joël Thierry Retornaz (born 30 September 1983 in Chêne-Bougeries, Genève, Switzerland) is an Italian curler from Cembra.

Although Italy has little curling tradition, and the sport was practiced only by a few hundred amateurs, Retornaz led the semi-professional Italian team to several unexpected victories over strong teams, including Canada.

[2] This breakthrough inspired a sudden national curiosity for curling, previously almost unknown in Italy.

Retornaz has represented Italy in ten World Curling Championships, in 2005, 2010, 2015, 2017, 2018, 2019, 2021, 2022, 2023, and 2024 skipping the team in each event except 2005.

Retornaz has competed for Italy in 16 European Curling Championships (as of 2024), finally winning a bronze medal in his 11th try in 2018, skipping the rink of Amos Mosaner, Sebastiano Arman, Simone Gonin and Fabio Ribotta.