In this paper we analyze the relationship between anxiety sensitivity (AS) and fear of flying. AS is one of the key elements of Reiss’ expectancy model and it is seen as an important risk factor for anxiety disorders. So far, specific phobias are the only anxiety disorder in which no clear evidence of a high AS has been found, as compared to non-anxious people,. The role of anxiety sensitivity was examined for the fear of flying in a non clinical sample of 523 subjects who were assessed with the Anxiety Sensitivity Index (ASI). An elevated AS was found among the subjects with fear of flying and a higher intensity of the fear of flying was associated with a higher AS. Most of the items of the ASI were useful in discriminating fearful from non fearful subjects. AS was related to variables of both severity of the fear and danger expectancies. No differences in AS were found when the fearful subjects were classified according to the principal component of their fear. Descriptive and psychometric data on the Catalan version of the ASI are reported.