Social disabilities due to mental disorders have a similar or even more severe impact on daily activities than some of the chronic, severe somatic disorders. The second version of the Groningen Social Disabilities Schedule (GSDS-II) is used in the assessment of social disability in persons with mental disorders. To date, in Poland the conducted research studies focused on this matter only in patients consulted in outpatient clinics and day units. Our study is the first in the country that aims to measure the social disabilities in persons hospitalized in psychiatric inpatient wards. The objective of the study is to assess the degree of social disability using GSDS-II as well as to analyze the impact of clinical, socio-demographic and economic factors on social disabilities in patients diagnosed with psychotic, mood or anxiety disorder (diagnostic codes: F20-F29, F30-F39 and F40-F48, according to ICD-10), aged 18–65, in a day unit and an inpatient ward settings. The excluding criteria are: substance abuse co-morbidity and/or a diagnosed dementia process. The study presents the data gathered from a sample of 50 patients of both genders diagnosed with the aforementioned mental disorders who gave their informed consent to participate in the study. Due to important socio-economic implications of mental disorders that frequently result in the loss of ability of the patients to fulfill their societal roles, a study leading to a better insight on social disabilities will provide useful data for the possible improvement of the mental health care and social policy designed for these persons.