The present study describes the psychometric properties of the Portuguese version of the Mental Health Inventory-5 for use with young adolescents. A sample of 367 Portuguese students (aged 10-15 years) completed the Portuguese-language versions of Mental Health Inventory-5 (MHI-5; Berwick et al., 1991), Children's Hope Scale (CHS; Snyder et al., 1997), Students' Life Satisfaction Scale (SLSS; Huebner, 1991a), and Global Self-Worth Sub-scale (Harter, 1985). Analysis of readability, reliability (internal consistency and 1-year stability), factor structure, and criterion-related validity suggested that the MHI-5 can be appropriately used in this age group. Implications of the findings are discussed.