In his psychobiological model of personality, Cloninger developed a novel approach concerning the relationships between psychopathological syndromes and personality. We investigated 207 chronic pain patients (CPPs) and compared them to 105 pain-free control subjects. Participants were assessed using the Temperament and Character Inventory (TCI), the Structured-Clinical-Interview-II, the Beck Depression Inventory and the Spielberger Anxiety Inventory. The CPPs scored higher on the depression and state anxiety scales and 41% fulfilled the criteria of having at least one personality disorder (PD). We used a covariance analysis to control for depression and state anxiety and found that the CPPs scored higher on the Harm Avoidance Temperament Dimension and lower on the Self-Directedness and Cooperativeness Character Dimensions. In CPPs, the symptom counts of all PD subtypes were significantly related to low Self-Directedness and, to a lesser degree, low Cooperativeness. The PD symptoms in Cluster A were related to low Reward Dependence, those in Cluster B were related to high Novelty Seeking and the PD symptoms in Cluster C were related to high Harm Avoidance. In multiple hierarchical regression analyses, controlling for age, gender, depression and state anxiety, TCI scales predicted on average 23% in PD symptom counts. The Self-Directedness and Cooperativeness personality traits appeared to be significant predictors in determining the presence or absence of a PD by correctly classifying 75.8% of CPPs. The TCI provides further insight into the mechanisms underlying the development of chronic pain. This useful diagnostic instrument helps to economically and validly facilitate the identification of core PD features.