Vasileos Konstantinos Avenue (Greek: Λεωφόρος Βασιλέως Κωνσταντίνου), Leoforos Vasileos Konstantinou, "King Constantine Avenue") is one of Athens' major thoroughfares running from the Panathinaiko Stadium (also known as the Kalimarmaro Stadium) at Herodou Attikou Street to the Hilton Athens on Vasilissis Sofias Avenue. It is a divided road with two lanes in each direction. The street is named after King Constantine I of Greece, who was King in 1913–1917 and again in 1920–1922.
Famous buildings on the street are the aforementioned Stadium, the National Gallery of Art and the Athens Hilton Hotel.