The team was founded as Centro Español de Instrucción y Recreación on 18 May 1897 by a group of Spanish immigrants resident in Chile.

In 1928, Unión Deportiva Española was awarded its second title, after winning the Liga Central de Fútbol.

In the next season, Unión had a youth squad during the Primera División tournament of 1940, but the team finished in the tenth place.

Under the Argentine Nestor Isella as coach, Unión Española was the runner-up of the Primera División Chilena in 1970, after a loss in the final match against Colo-Colo in January 1971.

In the season of 1973, with the arrival of the coach Luis Santibáñez to the club, Unión was proclaimed champion of Primera División for the second time, and the team had also the highest goalscorer of the tournament, Guillermo Yávar.

In the international tournaments, Unión had a poor performance during the Copa Libertadores 1973, finishing in the last position of the group stage.

In 1983, Unión made a poor season finishing in the 20th place of 22 teams, meaning the relegation to the Second Division.

Finally, the club not relegated because a decree of the directive of the Asociación Central de Fútbol (AFC).

Because the departure of Juvenal Olmos to Universidad Católica, the former player Leonardo Véliz arrived as coach in 2001.

In the second season of Carvallo in Unión, the club was eliminated in the quarter-finals of the play-offs by Santiago Wanderers, during the Torneo de Apertura, and in the Torneo de Clausura of the same year, Unión was runner-up of the tournament, after lossing the final against Cobreloa.

Because the departure of the coach Fernando Carvallo to Palestino, he was replaced by Fernando Díaz Seguel, with Díaz Seguel as the coach, Unión Española was champion of the Torneo Apertura 2005, winning the sixth title in Primera División in its history.

However, in the national tournament, Unión made a poor season, finishing in the thirteenth place of the Annual Table.

In 2008, under the Argentine Marcelo Espina as coach, Unión won his first three games of Torneo de Apertura 2008 against Deportes Melipilla, Audax Italiano and Universidad Católica, but on the next weeks the team worse his performance.

On July of the same year, the club was purchased by the Spanish employer Jorge Segovia for a fee of 2.500 million pesos.

In this play-offs, Unión won the tournament against Audax Italiano in the final, and the team qualficated to the 2011 Copa Libertadores First Stage against Bolívar.

The club's traditional rivals are Palestino, a team founded by members of the Palestinian diaspora living in Chile and Audax Italiano, which originated from their local Italian counterpart.

With Palestino and Audax, the team plays the so-called Clásico de Colonias ("Diaspora Derby").

Current squad of Unión Española as of 8 August 2024 (edit) Sources: ANFP Official Web Site Manager: Ronald Fuentes Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.

Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.

Unión Española is also the second oldest club of the Primera División Chilena behind Santiago Wanderers that was founded in 1892.