Backgroud: Trichomoniasis is not a reportable infection and its control received relatively little emphasis from public health STD control programs although it is the most common curable sexually transmitted disease in young sexually active women. Purpose: To diagnose trichomoniasis among women attending family planning units and to identify the possible risk factors affecting the disease. Materials and Methods: The present work was carried on 100 married women attending family planning units in EL-Fayoum Governorate. Diagnosis of trichomoniasis was done by direct wet mount microscopy, Geimsa staining and modified Field Stain. Results: The women ages ranged from 19 to 49 years old. The mean women age was 29.7± 7.1 years old. The majority of women (62%) had residence in rural areas and housewives (82%). The educational level ranged from illiteracy to high collage. Illiterate women were (14%). Seventy four women (74%) had educational level within 8 years of schooling. About 12% of women had high level education. Only six women (6%) had diabetes mellitus. The symptoms reported by the examined women include: (60%) increased vaginal discharge and itching, (31%) genital malodor. While (29%) women were presented with dyspareunia, (33%) presented with dysuria and (9%) with lower abdominal pain. This study demonstrated that Modified Field Stain (MF) stain, apart from being a rapid stain (20 s) in comparison to Giemsa stain (20 min.), confers sharper staining contrast, which differentiates the nucleus and the cytoplasm of the organism and demonstrated that Vacuoles are more clearly visible in parasites with MF than those stained with Giemsa. Conclusion: The results of the present study pointed to the benefits of use of modified Field stain in diagnosis of T. vaginalis infection.