Iceland participated in the Eurovision Song Contest 2004 with the song "Heaven" written by Sveinn Rúnar Sigurðsson and Magnús Þór Sigmundsson. The song was performed by Jónsi, who was internally selected by the Icelandic broadcaster Ríkisútvarpið (RÚV) in February 2004 to represent Iceland at the 2004 contest in Istanbul, Turkey. The Icelandic song, "Heaven", was presented to the public on 20 March 2004 during the television programme Laugardagskvöld með Gísla Marteini.

The Eurovision Song Contest 2004 was the 49th edition of the Eurovision Song Contest. It took place in Istanbul, Turkey, following the country's victory at the 2003 contest with the song "Everyway That I Can" by Sertab Erener. Organised by the European Broadcasting Union (EBU) and host broadcaster Turkish Radio and Television Corporation (TRT), the contest was held at the Abdi İpekçi Arena, and, for the first time, consisted of a semi-final on 12 May, and a final on 15 May 2004. The two live shows were presented by Turkish actors Korhan Abay and Meltem Cumbul. It was the first time that Turkey had hosted the contest, 29 years after the country made its debut, and was also the first time since the 1998 contest in Birmingham that it was not hosted in the host country's capital city.