There is an increasing need to understand epidemiology and risk factors of wildlife infectious diseases, especially for emerging zoonosis. The objective of this study was to investigate the major risk factors associated with the prevalence of Leptospira interrogans antibodies in wild lowland tapirs (Tapirus terrestris) in a seasonally inundated floodplain. The study was carried out in a private cattle ranch in the Brazilian Pantanal, Mato Grosso do Sul State (19º20''S; 55º43'W). Seventy-nine blood samples from 45 wild lowland tapirs (27♂ and 18♀) were collected between 2008 and 2014. Microscopic agglutination (MAT) was used to test the samples for 26 serovars of Leptospira spp. Antibodies against L. interrogans were observed in 65% (95% CI: 50-77%) of tapirs and 73% (95% CI: 63-82%) of tested samples. Nine L. interrogans serovars were found with considerably high antibody titers: Pomona 100–3200, Icterohaemorrhagiae 100–800, Bratislava 100–800, Grippotyphosa 100-400, Canicola 100, Copenhageni 100–400, Pyrogenes 800, Wolfii 200, and Hardjo 200. Age was negatively correlated with presence of L. interrogans (simple logistic regression; p<0.01) and juveniles presented lower infection rate (Fisher-Freeman-Halton test, p<0.01) when compared to sub-adults and adults. Higher titers of Pomona serovar were significantly correlated to the presence of other serovars (p<0.05) and to higher numbers of these (r=0.40; p<0.01). There were no significant differences when comparing sex (males and females), seasons (wet and dry) or locations with higher or lower volumes of water during the seasonal floods. Further statistical analysis will investigate temporal variation of antibody titers (for individuals captured and sampled multiples times throughout the study), spatial ecology (home range overlap) and kinship relationships. Despite the high antibody titers found in lowland tapirs, no clinical signs or laboratory results indicated disease in these animals. Nevertheless, potential health issues caused by exposure to Leptospira spp. should not be disregarded.