The prevalence of Theileria equi and Babesia caballi was determined in equid blood samples in five provinces of the Black Sea region of Turkey by using the indirect fluorescent antibody test (IFAT). Of 153 samples, 53 (34.6%) and 33 (21.5%) were seropositive to B. caballi and T equi, respectively. In addition, 8 (5.2%) of samples were seropositive to both T equi and B. caballi. Anti T equi and B. caballi antibodies were detected in all five regions. The prevalence of B. caballi was higher than T equi in all counties. Antibodies to T equi and B. caballi were detected in horses of all ages, and there were no significant differences among age groups. Out of 84 horses, 32 (38.0%) were positive for B. caballi infection and 20 (23.8%) were positive for T equi infection. Five horses (5.6%) were found to be scropositive to both B. caballi and T equi. Of 38 donkeys, 14 (3 6.8%) were found to be positive for B. caballi infection and 5 (13.1%) positive for T equi infection. In addition, 2 (5.2%) samples were seropositive for both T equi and B. caballi infections. Out of 31 mules, 8 (25.8%) were positive for B. caballi infection and 8 (25 8%) positive for T equi infection. One (3.2%) sample was seropositive for both T equi and B. caballi infections. Of all the animals in this study, only 3 horses were infected by Rhipicephalus turanicus and Hyalomma detritum, and no haemoparasites were detected by microscopic examination. (c) 2007 Elsevier Ireland Ltd. All rights reserved.