Introduction: It is widely recognized that young female sex workers (YFSWs) are at greater risk of HIV infection than their older counterparts. This study aims to unravel the complexities surrounding HIV transmission among this demographic group, by determining the prevalence of HIV infection and identifying high-risk sexual practices associated with HIV infection among YFSWs in Lubumbashi, in the Democratic Republic of the Congo. Methods: We conducted an analytical cross-sectional study and used a comprehensive sample of all YFSWs who presented to the HIV/Sexually Transmitted Infections Screening and Treatment Center in Lubumbashi between April 2016 and December 2017. We collected data on age, number of years in the practice of selling sex, number of sexual encounters per day, number of clients per week, systematic condom use, having suffered from sexually transmitted infections in the last 3 months before the survey, regular alcohol consumption, having anal sex in the last 12 months, having had forced sex in the last 12 months. Multiple logistic regression was used to identify potential factors associated with HIV infection. Results: A total of 572 YFSWs were included in the study, 19 of whom were HIV-positive (3.3%; 95% CI: 2.1% - 5.1%). Participants who were forced to have sex (adjusted OR=12.2; 95% CI: 3.2 - 46.4; p<0.0001), those who did not use condoms systematically (adjusted OR=4.1; 95% CI: 1.3 - 13.0; p=0.018), and those who had anal sex (adjusted OR=23.8; 95% CI: 6.9 - 82.4; p<0.0001) were more likely to be HIV-positive. Conclusion: The results of this study suggest that HIV prevalence among YFSW is higher than in the general Congolese population, and is significantly associated with high-risk sexual practices. Interventions aimed at increasing YFSW’s knowledge of high-risk behaviors should be vigorously pursued.