Unión Adarve resulted from a merger of two teams from Barrio del Pilar, ADC Adarve and Unión Barrio del Pilar (which was then refounded in 1983 in the place of AD Racing del Pilar). After several seasons in the Regional divisions, the club was promoted to Tercera División in 2007 by finishing in the third position of the 2006–07 Regional Preferente. In 2008 there was a change in the Board of Directors, José Ferreiro Feijó became the club's new president. With him Unión Adarve returned to Tercera División in 2011.[2]
In 2013, Unión Adarve qualified for the first time in the promotion playoffs, but was eliminated by CD Tropezón in the second round. After several other attempts, promotion was finally gained in 2017 with an away goals victory after a 4–4 draw with Atlético Malagueño.[3]
In the club's first Segunda División B campaign, they competed for the first time in the Copa del Rey, defeating neighbours CF Rayo Majadahonda 1–0 away in the first round on 30 August. In the next round away to UD Logroñés a week later, they lost 8–7 on penalties after a goalless draw.[4] And in the league the club managed to finish in the 11th position.[5] In May, 2019 the club appointed Javi Vázquez as head coach.[6]
