A -study Design, B -Data collection, C -statistical analysis, D -Data interpretation, E -Manuscript Preparation, F -literature search, G -Funds collection Background. autoimmune Polyglandular syndrome (aPs) forms a heterogeneous group of rare, genetically caused diseases, characterized by autoimmune activity against more than one endocrine organ, although non-endocrine organs can be also affected. aPs was classified into four types. the two major types are aPs-1 and aPs-2. Objectives. the aim of this study was to evaluate the type, number and sequence of appearance of autoimmune diseases forming different types of aPs in own material. Material and methods. the study involved 41 patients with aPs (32 F; 9 M), aged 19-72 years (mean 45.2 ± 13.5). the authors analyzed medical histories and the results of additional tests. Results. in the entire group of patients, as well as in each type of aPs, women predominated. the most frequently diagnosed type of aPs, confirmed in 51.2% of patients, was aPs-2. aPs-3 accounted for 41.5% of aPs. the most rarely observed, present in 7.3% of patients, was aPs-1. the most common pathology was autoimmune thyroid disease, followed by addison's disease, and third -type 1 diabetes. the majority of patients (58.5%) were diagnosed with only two coexisting disorders, mainly addison's disease and thyroid disease. in 36.6% of patients, three diseases were recognized, while four autoimmune disorders were discovered in only two women (4.9%). the onsets of consecutive autoimmune diseases in individual patients from study group were spread in time and spanned up to 29 years maximum. Conclusions. if the patient exhibits autoimmune disorders, the suspicion of a further autoimmune disease should be present. a family history of autoimmune disease is also very helpful. a patient with aPs needs life-long replacement therapy and observation by a family doctor, endocrinologist and other specialists to monitor the effectiveness of the treatment and detect new components of the syndrome. Key words: autoimmune polyglandular syndrome, aPs, autoimmune diseases, addison's disease, hashimoto's thyroiditis.