Mycoplasma hominis is a species of bacteria in the genus Mycoplasma. Along with ureaplasmas, mycoplasmas are the smallest free-living organisms known. They have no cell wall and therefore do not Gram stain. They are often present in the vagina, but may or may not belong to the normal vaginal flora. Some evidence suggests that M. hominis may be associated with pelvic inflammatory disease.
This species is known to frequently colonise the genital tract of sexually active men and women. This bacterium has also been associated with post-abortal and post-partum fever.
Growth of "fried egg" colonies on glucose agar medium within 24–48 hours is a characteristic of Mycoplasma hominis.