This quantitative study is to collect data of the knowledge of nurses about the Service for Assistance to women victims of sexual violence (SAMVVIS), in a public maternity hospital in Teresina, PI. Data was collected in February and March of 2008 from 61 nurses. The results show that the majority are aware of the service (90.14%) but the affirmative percentage decreases when asked about how it functions (80.33%, what its objectives are (72.13%), the role of the nurse (44.26%) and the proposal of the organization (40.98%). It follows that there is a need for the diffusion of the service, especially in the aspect of its objectives, the proposal of the organization and the role of the nurse along with national political attention for the women who are victims of sexual violence.