The Cartago Agrarian Union Party (Spanish: Partido Unión Agrícola Cartaginés) is a political party in Cartago, Costa Rica. The party was founded in 1969 by Juan Guillermo Brenes Castillo. It first contested a general election in 1970, but received only 0.5% of the vote and failed to win a seat. In 1974 support for the party more than doubled, receiving 1.2% of the vote and winning its first seat. Despite seeing its share of the vote drop to 1%, the party retained its seat in the 1978 elections. However a further slump to 0.8% in 1982 saw the party lose its parliamentary representation.