Background: Many patients with panic disorder meet criteria for at least one other diagnosis, most commonly other anxiety or mood disorders. Cognitive-behavioral therapy is the best empirically supported psychotherapy for panic disorder. There is now evidence indicating that cognitive-behavioral therapy for panic disorder yields positive benefits upon comorbid disorders. Objectives: The present study aimed to examine the predictors of broad dimensions of psychopathology in panic disorder after cognitive-behavioral therapy. Methods: Two hundred patients affected by panic disorder were treated with manualized group cognitive-behavioral therapy. We examined if the baseline personality dimensions of NEO Five Factor Index predicted the subscales of Symptom Checklist-90 Revised at endpoint using multiple regression analysis based on the intention-to-treat principle. Results: Conscientiousness score of NEO Five Factor Index at baseline was a predictor of four Symptom Checklist-90 Revised subscales including obsessive-compulsive (β = -0.15, P < 0.01), depression (β = -0.13, P < 0.05), phobic anxiety (β = -0.15, P < 0.05), and Global Severity Index (β = -0.13, P < 0.05). Conclusion: Conscientiousness at baseline may predict several dimensions of psychopathology in patients with panic disorder after cognitive-behavioral therapy. For the purpose of improving a wide range of psychiatric symptoms with patients affected by panic disorder, it may be useful to pay more attention to this personal trait at baseline.