INTRODUCTION AND AIM Primary Immune Deficiencies (PID) are rare but very severe hereditary pathologies associated with disfunction of immune system. The most common type of PID is Antibody Deficiencies (AD) that characterized by the recurrent bacterial infections in gastrointestinal, respiratory and urinary tract. The aim of the study was to analyze the data of pediatric and adult patients diagnosed as AD in our PID center between 2010-2019. METHODS All patients with PID were examinated by blood chemistry and phenotyping of immune cells in peripheral blood, measurement of IgM, IgG, IgA, IgE and sIgA levels in serum and saliva, phagocytic activity by NBT, and detection of CIC by photometric method. Additional X-ray and ultrasound examinations were also performed. RESULT In 2010-2020 years in Research Immunology laboratory of Azerbaijan Medical University patients suspected to immune disorders were examinated and the Antibody deficiency was detected in 46 patients: 3 adult and 6 children in age of 2-8 years were diagnosed with sIgA deficiency, Hyper IgM syndrome was rare deficiency-only in 2 chidren in age 1-2 years. The biggest group of patients with common variable immune deficiency and agammaglobulinemia included children of different ages and adults. All the patients who had frequent and severe infections-lung, skin, gastrointestinal diseases, were receiving replacement therapy-IVIG. Immune disbalance show decrease of quantity and function of B-cell, hypogammaglobulinemia. Detaled diagnosis in 5 patients based on the genetic tests which were carried out. The following results show genetic mutations: 2 case –Btk deficiency, 2 cases - CD40 LG deficiency, 1 case - BLNK gene mutation. CONCLUSION The children with repeated, severe bacterial infections and hypoglobulinemia have to be suspected on PID especially to AD type. Immune examination should be including serum immunoglobulin levels and B and T-cell subsets in peripheral blood as the first stage of detection.