Purpose <p>Adolescent motherhood is on the rise in developing countries, particularly in rural areas. This group faces unique vulnerabilities due to immaturity, fragile health systems, and limited access to information, making them susceptible to life-threatening diseases like breast cancer. This study focuses on breast cancer prevention and early detection knowledge among adolescent mothers in rural areas of Mvomero District in Tanzania.</p> Method <p>Using a cross-sectional design, 151 adolescent mothers from five health centers namely Mzumbe, Mikongeni, Konga, Tangeni Mission, and Mlali were interviewed, with data analyzed using descriptive statistics and the pairwise Wilcoxon signed-rank test.</p> Results <p>The findings reveal that while most adolescent mothers had experienced multiple pregnancies (64.90%), a vast majority (92.72%) had never been tested for breast cancer, with only 7.28% reporting testing. Significant gaps in knowledge and awareness were identified, with cultural stigmas, financial limitations, and systemic healthcare challenges serving as major barriers to effective prevention and early detection. The pairwise Wilcoxon signed-rank test further highlights significant differences between general knowledge, awareness, and actionable steps like prevention and early detection, emphasizing the difficulty adolescent mothers face in translating knowledge into practice due to these barriers.</p> Conclusion <p>Strategies such as peer-led education, adolescent-friendly healthcare services, and community-driven initiatives are recommended. Additionally, school-based health education, mobile clinics, and free or subsidized health services can enhance accessibility and engagement. Addressing these barriers is critical to empowering adolescent mothers with the knowledge and resources for breast cancer prevention and early detection, ultimately improving health outcomes and fostering individual and community well-being.</p>