A number of researches showed high prevalence of personality disorders among addicted gamblers. However, there are still few studies investigating the role of pathological personality facets in Gambling Disorder (GD). Moreover, the nature of the relationship between GD and pathological personality is not clear. We administered to a group of addicted gamblers (N = 79) and a group of healthy participants (N = 101) a battery of self‐report questionnaires encompassing the South Oaks Gambling Screen (SOGS), The Personality Inventory for DSM‐V (PID‐5), the Difficulties in Emotion Regulation Scale (DERS) and the Emotion Regulation Questionnaire (ERQ). Analyses of variance showed that addicted gamblers, compared to healthy participants, scored higher on most of the subscales of the DERS, on the Suppression Dimension of the ERQ and on the five main domains of the PID‐5 whereas they obtained lower scores on the Reappraisal subscale of the ERQ. Moreover, multiple regression analyses indicated that some specific facets of pathological personality, emotion dysregulation and lack of cognitive reappraisal, significantly predict GD's severity. Finally, emotion dysregulation levels and lack of cognitive reappraisal partially mediated the relationship between these and GD's severity. Our results confirmed the central roles played by both pathological personality and deficit in emotion regulation capacities in GD. Specifically, Impulsivity, Lack of Perseverance and Suspiciousness may be important predictors of GD severity. Moreover, emotion dysregulation and lack of adaptive emotion regulation strategies partially explained such relationship. As such, training for emotion regulation abilities appears strategically useful in the treatment of addicted gamblers with pathological personality traits.