Self-care agency is an important determinant of healthy aging. The Appraisal of Self-care Agency Scale (ASA-R) (Sousa et al., 2010) is one of the main instrument to assess self-care capacity. The objectives of the study were: 1) to adapt and validate ASA-R scale for use in Spanish population; 2) to examine the dimensionality, validity and reliability; 3) and to establish the convergent validity of ASA-R using a self-reported health measure. The ASA-R Scale and the 12-item Short Form Health Survey (SF-12) were administered to 488 Spanish seniors aged 65 and over. Confirmatory Factor Analysis (CFA) was used to analyze the dimensionality, validity and reliability. Convergent validity was tested by correlating the ASA-R factors with the SF-12 subscales; correlations were significant (p < .005). CFA showed that the ASA-R Three Factor Model fit well to the data, showing satisfactory fit indices, with S-Bχ2 > 0.05 (0.436), RMSEA closer to 0 (0.006), SRMR < 0.08 (0.065), GFI and AGFI close to 1 (0.924 and 0.921), and CFI and NNFI > 0.95 (0.996 and 0.995). The results also demonstrated that ASA-R is a reliable and valid instrument. The ASA-R has demonstrated to be a reliable (CR indices > 0.7) and valid (AVE > 0.5) instrument in measuring self-care agency among Spanish older population.