Chile, Colombia, Mexico and Peru formed the Pacific Alliance trading group last year in hopes of using their collective power to gain access to Asian markets.
Canada already has free trade deals with all four countries and is also working with three of them as part of negotiations for the 11-nation Trans-Pacific Partnership.
But talks for the TPP are only in the early stages and the government says being part of this new, smaller, group gives Canada another economic foothold in the region and in Asia.
Diane Ablonczy, the minister of state for foreign affairs, made the announcement Thursday in Columbia.
Ablonczy says having a stake in the group gives Canada an opportunity to shape prosperity in the Americas.