Joan Plaza Durán (born 26 December 1963) is a Spanish professional basketball coach, who currently serves as head coach of Zenit St-Peterburg of the VTB United League. He trained Real Madrid Baloncesto for three years, winning one Liga ACB championship, and an ULEB Cup (now called EuroCup) title. In 2009, after a bad season, he was replaced in Real Madrid, by CSKA Moscow's successful coach, Ettore Messina.
Joan Plaza began his career with the basketball school founded by him and his brothers, EB Betsaida. At the same time, he worked for the women's team EB Santísima Trinitat, as well as the small club CB Sant Adriá. In 1995, he at last became a new coach of Joventut de Badalona, where he worked as the youth and assistant trainer, until 2004. His greatest achievement was in the 2000–01 season, when his team won the Spanish Under-20 championship.
In the summer of 2004, following the wishes of the new coach Božidar Maljković, Plaza switched to Real Madrid. When the Serbian coach left after a disappointing season, Plaza assumed the position of head coach.