Born in Thessaloniki, Greece, Konstantinidis started his career playing with M.E.N.T.
Also, he won the Greek Championship for Cadets and Junior Men with PAOK, in 1978 and 1981.
He played seven years for PAOK first team, and he took part in two Greek Basketball Cup finals.
In 1984 Konstantinidis won the Greek Basketball Cup, after a memorable 84–80 victory against Aris.
Konstantinidis played five years at Philippos and he helped his club to win promotion to Greek Basketball League twice.