Trichomonas is a common protozoan that causes a sexually transmitted disease in humans called Trichomonosis and venereal and intestinal Trichomonosis in cattle and cats, respectively. This parasite also causes avian Trichomonosis, or canker, in birds' gastrointestinal tract. Three main pathogenic species (T. vaginalis, T. fetus, and T. gallina) belonging to this genus are identified and recorded in different parts of the world. However, their presence and epidemiology are still incompletely known in other parts, particularly in T. fetus in Iraq. This review aims to update information on this disease based on an electronic search of databases to document the presence and prevalence of Trichomonas spp. in humans and some animals in Iraqi cities. The findings show that the infection by T. vaginalis and T. tenax in humans and T. gallinae in birds are identified in Iraq, recording different percentage rates. However, venereal and intestinal Trichomonosis caused by T. fetus tends to be slight or absent in cattle and cats. Venereal Trichomonosis is only found in Basra and Nineveh provinces cattle, while intestinal Trichomonosis is not recorded in Iraq yet. T. hominis is recorded in central and northern areas of Iraq. In conclusion, less or absence of the infection in cattle or cats may be ascribed to animal breed, climate, less of studies, and/or other unknown factors. Thus, epidemiological and molecular studies are needed to investigate the presence and prevalence of this disease, particularly in cattle and cats of Iraq.