Black women continue to be disproportionally burdened by HIV. Pre-exposure prophylaxis (PrEP) is an effective HIV prevention option, which is underused by Black women. While social network interventions (SNIs) have been widely researched and implemented among some groups vulnerable to HIV, little is known about social network characteristics among Black women. To learn more about the social networks of Black women vulnerable to HIV and their knowledge of and interest in PrEP, we conducted a cross-sectional survey among 109 Black women aged 18-45 years attending a family planning clinic in Chicago, Illinois. In our study, 44% of women reported that they were moderately to extremely concerned about HIV. Over half of participants (53%) had a small personal network size (i.e., less than two). No statistically significant associations between having larger network sizes and having previously heard of PrEP, having an interest in starting PrEP, or having good PrEP knowledge were detected. Open-ended responses revealed high levels of trust in network connections with matters related to sexual health. Additionally, nearly all (94%) of women reported that SNIs were a good idea to promote PrEP. Future network studies are needed to inform the development of effective intervention strategies for women.