As the Personal Strengths Inventory (PSI) was developed to assess the strengths of adolescents, the Personal Strengths Inventory-2 (PSI-2) was developed so that children could be assessed as well. The present study examined whether the five-factor structure of the PSI would be demonstrated with the PSI-2 and whether the same measurement structure could be held across school levels and gender. The participants involved 2,325 (1,660 males and 665 females) students from elementary and secondary schools. The findings showed that the five-factor structure of the PSI-2 showed good fit and that there was factorial invariance across gender for boys and girls and partial invariance across school levels for elementary and secondary school students. The results are discussed in light of the call for strengths-based assessments, and further research is suggested.