Teaching proposals that enhance social and subjective aspects of various themes, previously restricted to the transmission of content, have gained prominence in the school curriculum through the subjects of science. Sex education, as one of these issues, has reached the school curriculum from the establishment of cross-cutting themes by the PCN in Brazil, and the science textbooks are one of its components. In this perspective, the objective of this study is to understand how the issueof STDs is presented in biology textbooks used at high school. We conducted a survey of collections, the planning of criteria for analysis and the examination of collections. The results show that the issue of STDs is presented in the books as additional information with emphasis on AIDS. There is no clear relation between the content of biology and the social context. Because of the limitations of the textbook, we propose to combine its use on the educational plan with additional strategies aimed at correlating the scientific knowledge at schools to contemporary social problems