Whilst alexithymia has been consistently linked to somatization, two prominent theoretical models lead to opposite predictions as to which of two proposed typologies of alexithymia will be particularly associated with somatic symptom reporting. In the present study, participants were recruited from a cross-section of the general adult population (n=301), and asked to complete a battery of self-report questionnaires which assessed alexithymia, somatization and negative affect. Collapsed across the whole sample, specific facets of alexithymia (enhanced fantasy life and difficulty identifying emotions) were significantly associated with somatization, and these pathways were perfectly mediated by negative affectivity. Further, type II alexithymia (impairment in the cognitive but not the affective dimension of alexithymia) was more predictive of somatization relative to type I alexithymia (impairment in both the cognitive and affective dimensions of alexithymia) and non-alexithymia (unimpaired in the cognitive and affective dimensions of alexithymia). The theoretical and clinical implications of these results are discussed.