The aim of this study was to investigate women s knowledge about and attitude toward emergency contraception (EC) in women who referred to health centers of Tehran University of Medical Science. The subjects in this study consisted of 250 married women of fertility age who had been selected randomly and interviewed by the researcher. The majority of the subjects had not used EC. Just 5.2% (13 women) had used this method and 8.31% had knowledge and information about EC. There was a significant correlation between knowledge about and use of this method (p = 0.0001). Although the users of this method were more knowledgeable about EC than nonusers, a majority of subjects (76.57%) had a positive attitude toward EC; however, there was not a significant correlation between positive attitude and use of EC (p = 0.184).