Littoral macrophytes from La Fe Reservoir (El Retiro, Antioquia) were sampled for ostracods during June and September 2008. This allowed the identification of four genera and six species of ostracods belonging to the Cyprididae and Candonidae families, where Chlamydotheca and Cypridopsis were found to be the dominant genera. Chlamydotheca unispinosa was the most abundant species in the assemblage. Furthermore, the environmental variables such as temperature, electrical conductivity, dissolved oxygen, and pH were also measured to establish their relation to ostracod taxa, using Canonical Correspondence Analysis (CCA). Results confirm the cosmopolitan character of Cypridopsis vidua and evidence the importance of plant substrate on the occurrence and distribution of the Cyprididae family. The possible application of the recorded ostracod assemblage in paleoenvironmental interpretations is discussed.