Jan Kosi (born October 18, 1996) is a Slovenian professional basketball player for Cedevita Olimpija of the Slovenian League. He is a 2.04 m tall Power forward.
Kosi started playing professional basketball for Elektra à  oà ¡tanj.
In September 2016, Kosi signed with Sixt Primorska.
On June 16, 2022, he has signed with Cedevita Olimpija of the Slovenian League.