Ethan Happ (born May 7, 1996) is an American-born naturalized Macedonian professional basketball player for Valencia of the Spanish Liga ACB and the EuroCup.

Happ is the all-time leading rebounder for the Wisconsin Badgers, where he started all 139 games of his college career and is the school record holder in double-doubles and triple-doubles.

[13] On July 18, 2019, Happ signed a two-year deal with the Greek EuroLeague club Olympiacos, of Piraeus, Greece, to play under head coach David Blatt.

[14] After appearing in only one game with Olympiacos, Happ was loaned on November 5, 2019, to the Italian League club Vanoli Cremona, for the remainder of the 2019–20 season.

[15] On June 30, 2020, the Greek club officially announced that they had forfeited their contract option and Happ thus became a free agent.

[19][20] On January 8, 2022, Happ signed with MHP Riesen Ludwigsburg of the Basketball Bundesliga (BBL).

After a lot of speculation about a possible move to Club Joventut Badalona or even a contract extension with CB Breogán, on June 29, 2023, Ethan Happ signed with EuroCup Basketball team Dreamland Gran Canaria for the 2023–24 ACB season.