Currently, there is no established measure to assess prolonged grief in adolescents. A new measure was designed based on the Extended Grief Inventory, the Inventory of Complicated Grief—Revised for Children, and the Inventory of Prolonged Grief for Children/Adolescents. We investigated the psychometric properties of the Prolonged Grief Questionnaire for Adolescents in a sample of 69 14- to 18-year-old parentally bereaved adolescents living in rural Rwanda. Additionally, we obtained sociodemographic information and assessed loss experiences and depressive symptoms. A principal component analysis revealed item loadings on two factors, which we named separation distress and secondary emotions. Internal consistency in this first evaluation was high (α = .94), and the criterion validity was satisfying. A sensitivity of 85.3% and a specificity of 85.9% were found. The small sample size is a major limitation. However, the Prolonged Grief Questionnaire for Adolescents may be a promising tool for assessing prolonged grief symptoms in adolescents.