Trichodinids are probably the most commonly encountered protozoan parasites on fishes in marine and freshwater environments. They are typically found on the gills, skin and fins of fish. The aim of this study was to evaluate the prevalence and mean intensity of Trichodina sp. in freshwater fish from cyprinid aquaculture facilities in Macedonia. This study was carried out by seasons, in a period of three years. A total of 578 specimens of common carp (Cyprinus carpio, Linnaeus 1758), 76 specimens of grass carp (Ctenopharyngodon idella, Valenciennes 1844), 47 specimens of silver carp (Hypophthalmichthys molitrix, Valenciennes, 1844) and 53 specimens of bighead carp (Hypophthalmichthys nobilis, Richardson, 1845) from the most significant and larger cyprinid aquaculture facilities in Macedonia, including fish farms and reservoirs, were examined for parasitological investigations. Infestation with Trichodina sp. was found in 206 specimens of common carp in all aquaculture facilities examined, in all seasons, as well as, in 9 specimens of grass carp from two fish farms, only in autumn season. Total, the prevalence with Trichodina sp. was 11.84% (grass carp) and 35.67% (common carp), while the, mean intensity was 7.56 (grass carp) and 4.56 (common carp). The prevalence with Trichodina sp. in common carp by season was as following: spring – 11.82%, summer – 3.44%, autumn – 7.85%, winter – 7.05%, while the mean intensity was: spring – 4.55; summer – 4.67; autumn – 4.40; winter – 4.72. Our findings of Trichodina sp. in grass carp in the present study is considered as the first record in Macedonia. Also, this fish species is regarded as new host for Trichodina sp. in Macedonian waters.