This study investigated factors hindering the implementation of career guidance in 10 secondary schools of Nyanza District, Rwanda. Using questionnaires and interviews with 159 teachers, 10 deputy head teachers, and 10 head teachers, data were analyzed through SPSS with a reliability score of 0.86. Findings revealed that unclear policies, lack of trained staff, educator workload, and class overpopulation limit effective career guidance. Additionally, some students showed unwillingness to be guided due to economic challenges or by imitating role models rather than pursuing their strengths. The study concludes that these barriers hinder proper implementation of career guidance in schools. It recommends the establishment of clear policies, monitoring, and training to strengthen guidance services.