The usefulness of the Mattis Dementia Rating Scale (MDRS) for Spanish dominant elderly adults has seen little empirical documentation, though there is considerable reason to hypothesize its value with this diverse and growing population. A Spanish adaptation of the MDRS (MDRS-SA) was developed for the present study in a manner to facilitate linguistic equivalence. Reliability for the MMRS-SA showed high split half internal consistency across all scales and Total Score. Two groups of elderly adults, one neurologically impaired and one not, both with low Mexican American acculturation level, Spanish dominance, and little formal education were participants. Results of a MANCOVA analysis, controlling for age, education, acculturation, and gender, showed the MDRS-SA to be effective at discriminating between groups across all scales (p <.001) and Total Score (p <.05). After determining significant differences between original norms and normative data an the present Spanish group, clinical utility of these statistical findings was investigated by generating specificity, sensitivity, and accuracy rates for the MDRS-SA Total Score, using Spanish normative data. Results of this preliminary study supported the MDRS-SA for use within the Mexican American, Spanish dominant elderly population though additional larger validation studies are needed, particularly with wed-documented clinical samples.