Preoperative evaluation was made of the diagnostic value of endoanal ultrasound (EAUS) and endovaginal magnetic resonance imaging (EVMRI) in diagnosing anal sphincter defects as the cause of anal incontinence. Nineteen female individuals with anal incontinence were examined clinically with EAUS and with EVMRI at 1.5 T using a prostatic coil. The findings were evaluated independently and compared with findings at surgery. In diagnosing external anal sphincter defects, EAUS and EVMRI showed almost similar agreement with surgical findings, 12 (63%) out of 19 vs 11 (58%), respectively. Internal anal sphincter defects were equally detected by EAUS and EVMRI as compared with surgical diagnosis. There was considerable variation between radiologists in diagnosing defects by EVMRI. EAUS and EVMRI are equal in diagnosing anal sphincter defects.