Mena finished his formation in
Santiago Wanderers' academy, and made his senior debuts in 2008
Chilean Primera División B. He scored his first professional goal on 11 October 2009, against
San Marcos de Arica. In July 2010, Mena signed with
Club Universidad de Chile, for a
$500,000 fee for the half of his rights. In his first season, Mena failed to break into a settled squad, appearing rarely. However, after the arrival of
Jorge Sampaoli in 2011, Mena was converted into an important player of the
La U squad. At the end of the season, he was a part of the squad which won
Copa Sudamericana and
Chilean Primera División. On 3 July 2013, Mena signed a one-year loan deal with
Brazilian Série A outfit
Santos FC, with a buyout clause. He quickly established himself as a starter, and on 5 June of the following year
Peixe bought the remaining rights of the player. On 14 January 2015, Mena rescinded his contract Santos, after winning a court case due to unpaid wages. Ten days later he agreed a deal with fellow league team
Cruzeiro. On 9 July 2018, he joined
Racing Club de Avellaneda. On 9 December 2022, Mena returned to Chile, joining
Universidad Católica, on a two-year contract. ==International career==