Background: HIV infection continues to wreak havoc around the world. Women are not spared, especially pregnant women, with low levels of education or information, transmitting HIV to their children. This study aims to assess the level of knowledge of women in reproductive age on the prevention of mother-to-child transmission of HIV / AIDS in the AFIA-Sake health area in the Democratic Republic of Congo. Method: This study is descriptive, involving 315 women aged 15-49 years from the AFIA-SAKE health area. The data collected by questionnaire were checked, captured and analyzed. The frequency of observations was calculated and the proportions were compared for accuracy when the CI was 95%. Results: The study shows that only 10% of women are aware of the prevention of mother-to-child transmission of HIV. Antenatal consultation is the excellent channel of communication. Among the women interviewed on antiretrovirals, 56% do not know when they will be given to pregnant women diagnosed with HIV; 63% do not know the value of administering antiretrovirals and 78% do not know when antiretrovirals will be given to the newborn. Conclusion: Achieving the goal of sustainable development for an HIV-free generation, with zero new infections in children and no HIV-related deaths, involves informing women of reproductive age about the prevention of mother-to-child transmission. HIV child through increased enrollment of girls, introduction of sex education as well as information on HIV in schools and antenatal clinics.