Candida species, Trichomonas vaginalis, and bacteria are considered to be the main causes of vaginitis. This study investigated the prevalence of candidal, trichomonad, and bacterial vaginitis and factors related to infection in women. This cross‐sectional study was conducted to investigate the relationship between different individual characteristics and common vaginal infections, namely, candidiasis, trichomoniasis, and bacterial vaginosis. The sample included all women referred to Allameh Bohlool Gonabadi Hospital women’s clinic in Gonabad in 2021. After the patient’s physical examination and questionnaire completion, samples were taken from the mucous secretions of the cervical vagina and the posterior fornix region using three sterile swabs. The first swab of secretions was placed on three glass slides for microscopic examination. At the same time, the second swab was transferred to the special Trichomonas culture medium (Dorset culture medium) available at the sampling site, observing sterile conditions. The third swab was placed in a test tube with a screw cap containing 5 cc of sterile physiological serum to be transferred to the laboratory. After adding two drops of potassium hydroxide (for elucidation), the first slide was examined under the microscope for the presence of Candida mycelia and buds. The second slide was used for warm staining to diagnose bacterial vaginosis. The third slide was used for Giemsa staining to detect Trichomonas. The swab in the screw‐capped tube was stretched in Sabouraud Dextrose Agar (SDA) medium and kept in an incubator at 35° for 48 h to detect Candida. The prevalence of candidal, trichomonad, and bacterial vaginitis in the admitting women was 5%, 38.5%, and 5.8%, respectively. A significant relationship was found between the history of vaginal infection, trichomonad infection, and candidal infection (p = 0.03). Moreover, significant relationships were observed between bacterial infection and the husband’s occupation (p = 0.002), methods of preventing pregnancy (p = 0.01), and menopause (p = 0.001). Vaginal infections are one of the common problems in women of all ages, and by knowing the factors that cause these infections, a big step can be taken to reduce the problem.