Introduction The present research aims to fill a gap in the national and international literature concerning prevalences and factors related to Bacterial vaginosis (VB) in Women who Have Sex with Women (WSW).

Methods It is a cross sectional, analytical and non-radomized study with 128 WSW from Botucatu - SP and surrounding regions who answered the call from social media, mass communication means, health services and friends or acquaintances from January to November,2015. Data was obtained by the researchers involved in the main study, through interviews ang gynaecological exam. The diagnostic of VB was abteined through gram staining. Associations were estimated by multiple regression.

Results The prevalence of BV was 41,1%% and factors associated were vaginal douching [OR=3,29 (IC:95%: 1,26–8,59) p=0014] and sex toys use[OR=2,34 (IC:95%: 1,00–5,50); p=0049].

Conclusion Considered as whole, these data lead to conclusion that the individuals of this study presented high vulnerability to STI/AIDS, as shown by the high prevalence of VB. This study clearly shows the need for a specific health assistance to these women, promoting prevention and education in a holistic approach.