In this study, we captured 60 wild New World monkeys (Cebus spp.; Alouatta caraya) at the Paraná river basin, Paraná State, Brazil, and modified agglutination test (MAT) was performed to evaluate anti-Toxoplasma gondii antibodies. Prevalence was 30.2% (13/43) in Cebus spp. (capuchin monkeys) and 17.6% (3/17) for A. caraya (black and golden howler monkeys). MAT showed antibody titers of 16 (15/16) and 64 (1/16). Herein, we have observed an odds ratio (OR)=4.67 (1.06<OR<21.42, p<0.01) among monkeys with presumed risk of human contact. There were not any statistical differences among age, species and sex (p>0.05). The present work is the first report on serum occurrence of anti-T. gondii antibodies in wild capuchin monkeys and in wild black and golden howler monkeys.