Eleni Papadaki (Greek: Ελένη Παπαδάκη; 1903–1944) was a celebrated Greek stage actress who was murdered at the end of World War II, accused of having collaborated with the Nazi occupation force.
She was born on 4 November 1903 in Athens to an affluent family, the granddaughter of university professor Stylianos Konstantinidis. She studied philology, phonetics, music and piano at the Great Conservatory of Athens, but began an acting career at the age of twenty-two in 1925, in Luigi Pirandello's Six Characters in Search of an Author. The theatre critic for the Demokratia newspaper greeted her performance with the comment that "today the stage has acquired a great actress". At the same time, she also performed in Oscar Wilde's Salome.
Her most successful performances during the last part of her career was in the ancient Greek tragedies.
After a twenty-year career on the stage, Eleni Papadaki was murdered in Athens on 22 December 1944, during the Dekemvriana events, by communists of the OPLA, accusing her of having collaborated with the German occupiers. She had been denounced by a rival actress.