Sexual Education is one of the transversal themes proposed in documents that govern Brazilian national education. However, even having legal support, in practice, teachers, in general, still have a lot of difficulty in approaching the topic in the classroom. The objective of this work is to study how public policies on sex education in schools and relations with science teaching are used through their National Curriculum (PCNs), the National Common Curricular Base (BNCC) of the Ministry of Education and Culture and Curricular Document for Goiás ( DG-GO). The study carried out was qualitative and characterized as a documental analysis with bibliographic research. It was found that the PCNs are of a transdisciplinary character that encompasses the social and biological factors of sexuality. However, the BNCC presents most of the biological skills only, which are worked only in the science discipline. In DC-GO, it has a biological focus, despite dealing with sex education in the arts and physical education curriculum component. Thus, the analysis documents found a setback in public policies aimed at sex education.