BACKGROUND: Toxoplasmosis, caused by Toxoplasma gondii, is a zoonotic disease affecting public health and wildlife conservation, including nonhuman primates. This study evaluated the presence of T. gondii in three neotropical tamarin species (Leontocebus fuscicollis, Saguinus geoffroyi and Saguinus oedipus) at Barranquilla Zoo, Colombia. METHODS: A retrospective analysis (2017-2022) was conducted on 17 tamarins. Clinical evaluations and blood samples were used to detect IgG antibodies via latex agglutination test. Necropsies and histopathological analyses were used to assess organ lesions associated with T. gondii. RESULTS: In 2017, 35% (6/17) of the participants tested seropositive, increasing to 100% (13/13) by 2022. Antibody titer fluctuations were noted, with significant increases in female S. oedipus. Four deaths occurred, two linked to active or chronic infections. Stray cats and rodents in the zoo were identified as possible transmission vectors. CONCLUSIONS: This study highlights T. gondii exposure to tamarins, associated mortality, and diagnostic challenges. Recommendations include stray cat management, pest control, and the exploration of vaccines to reduce transmission risks.