Bourousis originally began his athletic career training to be a professional swimmer, but he grew too tall for the sport, and so he took up playing basketball, at the age of 18.

Bourousis began his professional career in the year 2001, with AEK Athens of the Greek Basket League.

[6] However, he turned down San Antonio's offer, and instead signed a 3-year contract extension with Olympiacos worth €5.1 million euros net income.

In the summer of 2011, just weeks before signing with Olimpia Milano, Bourousis was involved in a doping-related media controversy in Greece, after an unrelated football match-fixing probe of his (then future) father-in-law, Makis Psomiadis.

[18] Real Madrid also eventually finished the season winning the 2014–15 Spanish League championship, after a 3–0 series score in the ACB Finals against Barcelona.

[20] On December 30, 2015, he was named Spanish League Player of the Month, after being MVP of the week three times in the first half of the 2015–16 ACB season.

[22] On May 23, 2016, he was named the Spanish League's MVP of the 2015–16 season, after averaging 12.9 points, 7.1 rebounds, 2.2 assists, and 0.9 steals per game.

Bourousis was a member of the Greek Under-20 junior national team that won the gold medal at the 2002 FIBA Europe Under-20 Championship, in Lithuania.

During an international friendly game between the national teams of Greece and Serbia, during the 2010 Acropolis Tournament, the Serbian player, Nenad Krstić, hit Bourousis on the head with a chair.