Greece participated in and won the Eurovision Song Contest 2005, its first Eurovision Song Contest victory. Greek national broadcaster Ellinikí Radiofonía Tileórasi (ERT) internally selected Helena Paparizou who sang "My Number One" in Kiev, winning the competition with 230 points. The song is written by Christos Dantis and Natalia Germanou, and composed by Christos Dantis. "My Number One" was selected through a national final on March 2, 2005, where the public and a professional jury chose it over three other candidate songs.

The Eurovision Song Contest 2005 marked Greece's twenty-sixth entry in the Eurovision Song Contest since its debut in 1974. Prior to the contest, its best result was third place which was achieved twice: in 2001 with the song "Die for You" performed by the duo Antique and in 2004 with "Shake It" performed by Sakis Rouvas. Greece's least successful result was in 1998 when it placed twentieth with the song "Mia Krifi Evesthisia" by Thalassa, receiving only twelve points in total, all from Cyprus.

The Greek national broadcaster, Ellinikí Radiofonía Tileórasi (ERT) broadcasts the event in Greece each year and organizes the selection process for its entry. Its selection techniques have varied from national finals where the public selects the entry, to internal selections like used in 2004, where the broadcaster has complete control over the selection. For the Eurovision Song Contest 2005, ERT decided to hold a televised national final after internally selecting an artist.

Throughout the months preceding the national selection, rumors flooded Eurovision news websites about which artist would be representing Greece in the Eurovision Song Contest 2005. There was an internal selection for the artist, being chosen by the broadcaster, while there would be a national final for the song, with the public having a say in the choice.

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