Anxiety disorders are highly prevalent, highlighting the need for the development of instruments that measure validly and efficiently anxiety disorders and related problems. According to predominant theories on emotion, there are cognitive, physiological and behavioral responses that are characteristic of fear-related responses. However, most of the instruments aimed at evaluating public speaking anxiety (PSA), focus exclusively on one or two of these aspects. The PSA Scale was developed to measure cognitive, behavioral and physiological dimensions of fear related responses. The goal of the present study was to assess the internal consistency and the factorial structure of a Spanish version of the Public Speaking Anxiety Scale. Consistent with the original version, we found a high internal reliability, and a two-factor structure, which is discussed in the light of up-to-date theory on emotion. Finally, our study provides definitive information on support of the reliability of the PSA-S, and on its clinical utility to assess PSA in a Spanish speaking population.