AD Almería was a team that played in La Liga between 1979–81, but disappeared in 1982, and was arguably UD Almería's predecessor. In 1989, a club named Almería Club de Fútbol was born, but in 2001 was renamed Unión Deportiva Almería. After playing one season in the second division, it was relegated to the third and the fourth divisions.

After spending several seasons in the second level, Almería side was first promoted to the top flight after finishing runner-up in the 2006–07 season. After some outstanding performances, the team achieved a final 8th league place in 2007–08. At the club's helm was coach Unai Emery, as striker Álvaro Negredo finished team topscorer with 13 goals.

After Emery left for Valencia CF, Gonzalo Arconada stepped in, but was sacked on 21 December 2008, after a string of poor results, albeit without ever reaching the last three. Mexican Hugo Sánchez took the job, and fared slightly better, for a final mid-table position.

In 2010–11, Almería reached the semifinals of the Copa del Rey for the first time ever. In the league, however, the club was finally relegated after a four-year spell in the top flight; in November 2010, coach Juan Manuel Lillo was fired after a 0–8 home loss against FC Barcelona (precisely the team that ousted the Andalusians in the domestic cup's last-four, with the same score, but on aggregate), and his successor José Luis Oltra met the same fate, in April 2011.

After two seasons in the second level, Almería returned to the main category of Spanish football on 22 June 2013, after defeating Girona FC in the play-offs. After the departure of manager Javi Gracia, the club appointed their former player and manager of the reserves at the time Francisco; the team eventually managed to survive in 2013–14, finishing 16th.

Francisco was sacked in December 2014, after only managing two points out of 24, and was later replaced by Juan Ignacio Martínez. "JIM" also only lasted until April of the following year, and even with new manager Sergi Barjuán, the club was relegated after finishing 19th.