Background: Multiple Sclerosis is one of the leading autoimmune disorders causing disability among young adults. Various types of mood, affect, and behaviour disorders along with cognitive impairment can be manifested in a course of MS, with affective and anxiety disorders being the most prevalent. Mental health challenges, in addition to the neurological burden of MS, significantly affect quality of life and the course of the underlying disease. Objective: The aim of this work was to determine the prevalence of mental disorders in a sample of MS patients during outpatient treatment in Zabrze, Poland, with a focus on those with mood and anxiety disorders, and to compare the results obtained in these groups with clinical and sociodemographic data. Method: The study was conducted between 2017 and 2018 on 103 MS patients of the Neurological Outpatient Clinic of the Medical University of Silesia Hospital No.1 in Zabrze, Poland. During the study, sociodemographic data were collected, as well as the type and course of the underlying disease, comorbidities, and medicines used. The MINI-international neuropsychiatric interview and a psychiatric examination were utilized to assess the occurrence of mental disorders. Result: 68% of all patients received a psychiatric diagnosis at some point in their life with only 4% having been hospitalized before; 49.5% met the diagnostic criteria for various psychiatric disorders. Measured by the MINI International Neuropsychiatric Interview, 33% of patients reported a past episode of major depression while 8.7% met the criteria for a current episode. The same number of patients admitted ongoing treatment due to recurrent depressive disorder. In regards to anxiety disorders, the most common was generalized anxiety disorder (10.7%), followed by agoraphobia (8.7%), panic disorder (7.8%), and social phobia (4.9%). Most of the patients (94.2%) at the time of the psychiatric evaluation presented a low level of suicide risk, while 1.9% of the patients presented a medium risk, and 3.9% - a high risk. Conclusion(s): The study confirmed a significantly higher prevalence of mental disorders among MS patients; thus, the psychiatric state of patients in this group should be investigated systematically, simultaneously with the assessment of their neurological state. Trial registration: N/A Key words: Multiple Sclerosis, psychiatric disorders, comorbidity, psychiatric care, clinical characteristics.