Background: Psychological disturbances are well-known disorders in patients with hyperthyroidism, with anxiety and depression being the most commonly described. Stressful life events may play an important role in the relationship of anxiety, depression and hyperthyroidism. We assessed the associations of these disorders by three-part rating scales, including the Hamilton Rating Scale for Anxiety (HAM-A) indicating anxiety, the Zung Self-Rating Depression Scale (Zung Scale) indicating depression and the Social Readjustment Rating Scale (SRRS) indicating external stress from life events in this study. Methods: Eighty-six outpatients who visited an endocrine clinic with suspicion of thyroid disease and 18 healthy volunteers were enrolled in the study. In all of these individuals, thyroid functions were assessed and questionnaires were completed during an interview. Results: The outpatients with hyperthyroidism (n = 39) had higher scores of HAM-A (15.7 ± 1.1 vs. 8.0 ± 0.8, p < 0.001), Zung scale (46.2 ± 1.5 vs. 37.5 ± 1.4, p < 0.001) and SRRS (92.9 ± 13.5 vs. 56.9 ± 8.4, p = 0.015) than those with euthyroidism (n = 47). The scores of the three-part rating scales were also higher in the outpatients with hyperthyroidism than in healthy volunteers (n = 18), with no significant differences between the outpatients with euthyroidism and healthy volunteers. Conclusion: In patients with hyperthyroidism, anxiety, depression and stressful life events were more severe than in those with normal thyroid function. There were no correlations between these psychological disorders and thyroid function tests of the subjects with hyperthyroidism. The role of psychotherapy in the development of hyperthyroidism deserves further investigations.