Panionios G.S.S., the Pan-Ionian Gymnastics Club of Smyrna, is a Greek multi-sport club founded in 1890. Originally based in Smyrna/Izmir, the club was uprooted in the population exchange between Greece and Turkey following the Asia Minor Catastrophe in 1922. It is now based in the suburban town of Nea Smyrni, located in the Attica, and where many of the refugees from Smyrna settled.

Panionios G.S.S. Football Club, the Pan-Ionian Gymnastics Club of Smyrna, more commonly known as Panionios F.C. or simply Panionios, is a Greek football club based in Nea Smyrni, a suburban town in the Athens agglomeration, Greece. Part of Panionios G.S.S., Panionios F.C. is the oldest Greek football club.