The club was founded on 1 March 1886 by a group of fifteen people who met at the Cafè del Centre on Rambla Nova. The majority of the club's early members belonged to the upper middle classes and, as the club name suggests, it was initially founded to promote gymnastics. Later the club members also began to organise fencing, hiking, boxing and cycling. In 1914, the club absorbed a local football club called Club Olímpic de Tarragona and consequently formed its own football team, using the former colours of Olímpic: red, white and black. In those days, it played home matches in the Avenida Catalunya stadium.
After returning to the second level Gimnàstic achieved a mid-table position in 2007–08 and 2008–09, with César Ferrando being in charge of the team. However, in the 2009–10 and 2010–11 seasons, the club only managed to rank one position above the relegation zone, and, in the 2011–12 campaign, was relegated to Segunda División B after only winning six games out of 42.
On 12 September 2012 Nàstic won the second Catalan Cup in its history, after defeating AEC Manlleu with an Eugeni goal.