To study the using rate and demographic characteristic of female patients attending in Rajavithi Hospital who used coitus interruptus (CI) as a contraceptive method.Two hundred sexually active, reproductive age (15-44 years) female patients attending family planning, postpartum or gynecologic clinic in Rajavithi Hospital between March 1, 2004 and May 31, 2004 were interviewed to obtain demographic data and CI using designed questionnaires.One hundred and forty out of 200 women were using CI as a choice of contraception (70%). The mean age of the CI groups was 27 years. Most were occupied as private sector employees (49.3%). Friend was the most common route for obtaining information about CI (46.4%). The women and their partners were satisfied with CI 68.6% and 34.3%, respectively.Seventy percent of the female patients seeking services at Obstetrics and Gynecology Department in Rajavithi Hospital used CI as a choice of contraception. Friends were the most common route for obtaining information regarding this contraceptive method (46.4%).