The Croatian participating broadcaster, Hrvatska radiotelevizija (HRT), organised the national final Dora 2004 to select its entry for the contest.

In the final, "Daješ mi krila" performed by Ivan Mikulić was selected as the winner following a regional televote.

Since 1993, HRT organised the national final Dora in order to select its entry for the contest, a method that was continued for its 2004 participation.

Votes cast via landline were divided into five telephone regions in Croatia, each of them which created an overall ranking from which points from 1 (lowest) to 12 (highest) were assigned to the competing songs.

[6] On 3 December 2003, HRT opened a submission period where artists and composers were able to submit their entries to the broadcaster with the deadline on 17 January 2004.

A seven-member expert committee consisting of representatives of HRT: Željko Mesar, Aleksandar Kostadinov, Željen Klašterka, Tomislav Štengl, Zoran Brajša, Marin Margetić and Dubravko Češnjak reviewed the received submissions and selected twenty-four artists and songs for the competition.

[12] The winner, "Daješ mi krila" performed by Ivan Mikulić, was determined by a public televote divided into regional and mobile phone votes.

According to the rules, all nations with the exceptions of the host country, the "Big Four" (France, Germany, Spain and the United Kingdom), and the ten highest placed finishers in the 2003 contest are required to qualify from the semi-final on 12 May 2004 in order to compete for the final on 15 May 2004; the top ten countries from the semi-final progress to the final.

[14] Ivan Mikulić performed the English version of "Daješ mi krila" at the contest, titled "You Are the Only One" (formerly "You Were My Only Love").