Immunodeficiency diseases have a significant impact on morbidity and mortality rates of the population due to the chronic relapsing course and resistance to therapy. In Moldova, there is no National Register of primary immunodeficiencies International Journal on Immunorehabilitation 2019 Volume 21 No 1 XI I WORLD ASTHMA, ALLERGY & COPD FORUM  XI I WORLD CONGRESS ON MOLECULAR ALLERGOLOGY, IMMUNOLOGY & ASTHMA St Petersburg, Russia June 29 – July 2, 2019 ISSN 1562-3629 17 (PID) and the latter appear under the “mask” of various nosological forms. The purpose of this work was to develop basic criteria for the diagnosis of primary immunodeficiencies at the level of the Center for Family Doctors. Six hundred and s eventy cards of complex medical examinations of patients with suspected PID were analyzed using clinical, instrumental, laboratory tests (complete blood count, immunogram with determination of population content and lymphocyte subpopul ations, serum immunoglobulin classes M, G, A, E-total) and others. Based on the multivariate analysis, the most informative basic criteria for identifying PID at the primary health care level were selected, which included risk factors, nosological forms proposed by WHO, a history of the disease, data of an objective examination of the patient and laboratory test results. PID was characterized depending on age (in newborns and babies aged 5–6 months, in children aged 6 months –5 years, in children aged 5 and adults). There were identified 21 cases of PID of which 11 were confirmed by molecular genetic methods. Thus, the use of these criteria will contribute to the early detection of patients with suspected PID, and a comprehensive clinical, immunological, and molecular genetic examination confirms the diagnosis at the tertiary level of medical care.