Spain was represented by Peruvian-born singer Betty Missiego at the Eurovision Song Contest 1979, held in Jerusalem, Israel. Missiego was selected internally by Radiotelevisión Española (RTVE), the Spanish broadcaster, to represent the country at the contest in Israel with the song "Su canción".

Missiego closed the contest, performing 19th in the running order, following Austria. Missiego performed the song with four children who joined her as backup singers of sorts; they were Javier Glaria, Alexis Carmona, Beatriz Carmona, and Rosalía Rodríguez. At the close of voting Missiego had received 116, placing 2nd.

Ironically, Spain was the last country to vote and Missiego had been leading the contest until Spain awarded Israel 10 points, granting Israel the win.

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