Aim. The aim of the study was to assess working memory and executive dysfunctions, as well as the intensity of depressive symptoms in hyperthyroid patients with Graves' disease compared to healthy persons. Method. Thirty (30) patients with Graves' disease (20 female, 10 male), aged 18-55, participated in the study. The control group consisted of 31 healthy persons matched by age, gender and educational level with the examined group. The assessment of working memory and executive functions was estimated by the Wisconsin Card Sorting Test and the N-back test. The intensity of depressive symptoms was assessed by the Beck Depression Inventory. Results and conclusions. In comparison to healthy subjects, significant disturbances of working memory and executive functions were noted in hyperthyroid patients with Graves' disease. Longer disease duration was associated with worse results in neuropsychological tests, while higher educational level of the patient resulted in better test outcomes. In the group of patients with Graves' disease, 1/3(rd) of them presented with a significant intensity of depression symptoms; additionally, the intensity of depression symptoms correlated with cognitive function impairments in the whole group of the patients studied.