The article describes the psychometric analysis of the APGAR Scale developed by Smilkstein (1978), consisting of five Likert items with five alternatives, which evaluates the perception of family functioning (Gómez & Ponce, 2010). The scale was administered to 256 male students aged from 11 to 18 attending state school in Lima. Item-test correlation analysis provided evidence of highly significant relations (p<0.001) for each of the reagents, indicating that reagents evaluate indicators of the same construct. To assess the perception of family functioning, APGAR Scale has moderate internal consistency (Cronbach a = 0.788). Construct validity was established by factor analysis and a single factor was obtained through a principal component analysis and the orthogonal rotation (Varimax).